HUMAN GROWTH HORMONE
(HGH)
written by Jerry Emanuelson
[email protected]
Latest revision: April 14, 2010
Important Note: Many people come directly to this chapter from a search engine without realizing that it is one chapter of an online Life Extension Manual. If you are interested in this subject, please read the rest of the Manual as well, beginning with the important Preface to the Life Extension Manual.
The average person thinks of the damage of aging as an inevitable process of wear and tear. However, if wear and tear were the primary cause of aging in humans, a 60 year-old should have only twice the signs of aging as a 30 year-old.
Why do most 30-year-olds show few effects of aging, while the effects of aging are so obvious in a 60 year-old person? If wear and tear were the major cause of aging, a 90-year-old person would only have 3 times as much aging damage as a 30-year-old.
At the age of 30, people have spent most of their lives with fairly high levels of human growth hormone (HGH). HGH is responsible for growth during childhood -- and for the repair and regeneration of human tissue throughout our lives. By the time we reach the age of 30, our HGH levels are only about 20 percent of their peak levels during childhood, and after the age of 30, they continue to decline at about 12 to 15 percent per decade, and often much more. By the time most of us are 30 years old, our bodies no longer produce enough HGH to repair all of the damage that is occurring in our bodies. As our HGH levels continue to decline, the damage that we call aging continues to accelerate.
The decline in HGH is not the only cause of the manifestations of aging. Even if our HGH levels remained at the level of a 25 year-old, we would continue to experience the effects of aging, but those effects would be greatly reduced until we reached a very advanced age. HGH does not affect the root cause of aging, as measured by maximum lifespan, but it can certainly affect many of the manifestations of aging.
By increasing the levels of HGH in our bodies, we can slow, or even reverse, many of the manifestations of aging. It must be done carefully, though, and under medical supervision. Ideally, this HGH replacement should begin at about the age of 30 years, but HGH replacement can be beneficial at any age above 30. In fact, for older people, HGH therapy can reverse the manifestations of aging by 5 to 15 years or more. There is no other single therapy currently available that can have the impact on the aging body that HGH can have.
What HGH therapy can do:
* Reduce excess body fat, especially abdominal fat. (The reduction of abdominal fat is the single most profound effect of HGH replacement in many people.)
* Increase muscle mass (and physical strength if combined with moderate exercise).
* Reduce wrinkling of the skin and some other effects of skin aging.
* Re-grow certain internal organs that have atrophied with age.
* Increase bone density.
* Strengthen the immune system.
* Reverse cognitive decline.
* Stimulate production of the bone marrow cells that produce red blood cells.
* Reduce the probability that you will spend the last years of your life in a nursing home.
* HGH slows the progression of cardiovascular disease, and reduces the risk of death from cardiovascular disease, in individuals with natural growth hormone levels that are below average for the age of the individual. HGH can also slow the progression of cardiovascular disease by improving one's cholesterol profile. There is increasing evidence over the past year or two that maintaining healthy growth hormone levels results in a stronger heart. Individuals with low growth hormone levels have an overall increased risk of death due to cardiovascular disease. Low growth hormone levels cause a particularly large increase in the risk of stroke as compared with individuals receiving growth hormone replacement.
What HGH cannot do:
* It cannot eliminate the effects of oxidation damage, although it may alleviate some of it.
* HGH cannot eliminate the effects of the reduction of other hormones. In fact, a deficiency of certain other hormones will decrease the beneficial effects of HGH.
* It cannot significantly reverse the damage to human proteins caused by glucose, although it may reverse a little of this damage.
* Although it helps skin to look younger, it cannot eliminate all of the damage cause by sunlight and other ultraviolet sources.
* It cannot increase maximum lifespan. For many people with HGH or IGF-1 genetic defects, however, it can significantly extend life expectancy.
Note: As of this writing, there is a federal law in the United States that prohibits the use of human growth hormone for any purpose outside of a very narrow range of conditions. At the beginning of 2007, the federal government made some attempts to start enforcing this previously obscure law. This caused great human suffering and several deaths.
I can give a personal example of the health damage caused by the prohibition on the "off-label" use of HGH. I have a strong genetic tendency toward spinal osteoporosis, which the evidence strongly suggests is IFG-1 related. (IGF-1 is produced in response to growth hormone.) My father died very slowly of the effects of this disease as his spine crumbled away. The FDA does not recognize this condition, and federal law prohibits the use of HGH against osteoporosis unless damage to the pituitary gland can be demonstrated. As a result of FDA attempts to enforce this law, I spent 6 months without HGH. During this period, I lost 8 percent of the bone mineral density of my L1 vertebrae, more than 10 percent of my L2 vertebrae, and more than 21 percent of the density of my L3 vertebrae. During this same period, I crossed the threshold from spinal osteopenia to spinal osteoporosis. I am quite healthy otherwise. I subsequently obtained medical care outside of the United States in order to avoid further spinal deterioration. By taking control of my own medical care, I have been able to substantially regain much of my loss of spinal bone mineral density.
Many doctors in the United States simply ignore the law prohibiting the uses of HGH for conditions not specifically approved by the FDA. Any doctor who does so, however, is risking legal problems. Although it is almost impossible to actually convict any physician for prescribing HGH for any medical condition (because juries are more compassionate than government bureaucracies), the federal government has tried, and such attempts have been financially very costly for physicians.
HGH is produced by the pituitary gland. The ability of the pituitary gland to produce HGH declines very little with aging in most people. The decline with aging occurs one step back from the actual secretion of HGH by the pituitary. There are at least 3 substances which control HGH secretion:
* Growth hormone releasing hormone (GHRH), a substance which declines with age. Increasing levels of GHRH causes the pituitary to increase its output of HGH.
* Growth hormone releasing peptide (GHRP) is another substance that declines with age. Increasing levels of GHRP also causes the pituitary to increase its output of HGH.
* Somatostatin is a hormone that blocks the release of HGH by the pituitary gland. The natural production of somatostatin increases with age, and causes a corresponding decrease in HGH production by the pituitary gland.
The production of HGH is controlled by GHRH, GHRP, somatostatin, and other substances in the body. The degree to which changes in the levels of each of these substances is responsible for the decline in human growth hormone varies from individual to individual, and is somewhat gender-dependent.
The only naturally-occuring growth hormone releasing peptide appears to be ghrelin. Ghrelin is a hormone with many other effects, including being a powerful appetite stimulant. When given to laboratory animals, the animals eat huge amounts of food. The weight gain induced by overeating completely overwhelms the fat burning caused by the growth hormone release, and the animals become obese. Pharmaceutical companies have produced synthetic growth hormone releasing peptides, such as GHRP-6 and GHRP-2, which stimulate HGH in humans, but do not increase appetite significantly. These substances are not on the market yet, and probably won't be for many years, if ever.
Pharmaceutical companies have produced a number of other promising analogs of ghrelin that restore the normal pulsatile release of growth hormone without the other unwanted effects of ghrelin. These substances include:
* Hexarelin
* MK-0677 (ibutamoren mesylate, developed by Merck)
* Capromorelin (developed by Pfizer)
* Tabimorelin
* SM-130686 (Sumitomo Pharmaceuticals)
* Ipamorelin (Novo Nordisk)
* NN703 (Novo Nordisk. Similar to ipamorelin, but more selective)
Many of the above growth hormone releasing analogs of ghrelin are effective when taken orally. None of them are on the market anywhere in the world. Hexarelin is a peptide that is fairly easy to synthesize, and it is sometimes used outside of legitimate medical channels. The other substances on the above list are only available in rare clinical trials.
Even though the above compounds have all been researched and found effective, it is doubtful if the research will proceed much farther. Most of these compounds are mainly effective against age-related declines in growth hormone. The United States Food and Drug Administration (FDA) does not regard the age-related decline in growth hormone to be a disease, even when it results in serious disability and death. Because of the size of the U.S. market and the worldwide influence of the FDA, these valuable medicines will probably be forever blocked from the market. (Because of the effectiveness of MK-0677, however, there is some hope for it eventually being approved somewhere in the world for a condition other than age-related growth hormone decline.)
Three major analogs of growth hormone releasing hormone have been developed by pharmaceutical companies, and will be discussed later:
* Sermorelin (Geref, developed by Serono, withdrawn from the market)
* Tesamorelin (Theratechnologies)
* CJC-1295 (ConjuChem Biotechnologies)
The effects of HGH in the human body have been studied intensively for decades, but the factors that affect HGH production remain rather complex and mysterious. Part of the reason for this is that the quantities of these substances produced by the body are on the order of a milligram per day in adults. Most people only produce about a teaspoonful of these substances during their entire adult lives.
To make the HGH situation even more complex, HGH is normally released in pulses or bursts throughout the day. There are usually 10 to 20 surges of HGH release, with the largest release occurring shortly after you fall asleep. Is there any advantage to having HGH released in pulses? Or is this simply the body's most efficient way of producing HGH? Nobody knows the answer to this important question.
There are indications, however, that some of the ghrelin analogs or the GHRH analogs may be superior to ordinary HGH replacement. Ordinary HGH therapy does not increase insulin sensitivity or decrease glucose levels, although it logically should be expected to -- since it increases the level of IGF-1 (insulin-like growth factor number 1). IGF-1 decreases glucose levels, so there is something about the continuous presence of growth hormone that is offsetting this IGF-1 related decrease in blood glucose. When youthful pulsatile release of growth hormone is restored, often (most notably with Tesamorelin) the IGF-1 related decrease in blood glucose is seen, as would be expected.
There are three basic ways for increasing HGH:
* Taking a substance that increases the natural secretion of HGH by the pituitary gland.
* Using an injectable human growth hormone releasing hormone (GHRH).
* Using injectable human growth hormone.
With current technology and available substances, taking a substance that increases the natural secretion of HGH generally works best for those between the ages of roughly 30 to 45 years.
For most people over 45, injectable HGH is most effective -- and usually the only effective -- of the currently available options (although sermorelin works for some people). Tesamorelin looks like it will be very promising when it becomes available. But let's look at these three methods in greater detail.
There are a number of substances that increase the natural secretion of HGH. Some of them are amino acids. The relationship of certain amino acids to growth hormone is complex and varies greatly among different individuals and among individuals of different ages. All absolute and universal statements made about this subject are clearly false.
The most effective and economical way of causing this HGH release for many people seems to be taking 2 grams of the amino acid L-glutamine in the morning and taking 10 to 30 grams of the amino acid L-arginine before bedtime. Both of these amino acids must be taken on an empty stomach. Amino acids are generally not very effective in people over the age of about 40 to 45. In fact, for people over about the age of about 40 to 45, HGH increases due to amino acids may only be barely measurable on laboratory tests, and may have no real practical effect.
There has been only one scientific study showing that L-glutamine causes HGH release, but there is a large body of anecdotal evidence from anti-aging physicians and their patients that L-glutamine is actually effective in most persons under about age 45.
There is a large body of scientific study on the effects of L-arginine on growth hormone release. In fact, the administration of a large dose of L-arginine is a standard test for the ability of the pituitary to release growth hormone. (Another test using insulin is actually more effective, but it is not accepted as the standard test by the U.S. Food and Drug Administration.) Most scientists believe that L-arginine promotes HGH release by inhibiting somatostatin, and this has been demonstrated in at least one scientific study. L-arginine has many other benefits in addition to being a growth hormone releaser. See the chapter of this manual on Arginine for additional information about using arginine as a growth hormone releaser and for safety warnings about the use of arginine.
There are several problems with the use of arginine and other amino acids as HGH releasers. Their effectiveness generally diminishes with age, and with continued use. This has led some people to the opinion that amino acids such as L-arginine are weak or ineffective HGH releasers. This can be a dangerous assumption. In some young people, L-arginine may actually cause dangerously high levels of HGH release. Many young people use L-arginine, but it should not be used by anyone until at least 5 years after they have completed their long bone growth (unless they are under close medical supervision).
I personally know of one 19 year-old female who took L-arginine (about ten grams) before bedtime for one week. She stopped after one week because it was making her nauseous, which was an indication of an excessive level of HGH release. Even though she had not grown since she was 16, during the subsequent month, she grew an additional inch, and had a noticeable growth of her heel bones.
(Please note that this is an article about HGH replacement in adults. Please don't ask me questions about using HGH for gaining height. There are plenty of endocrinologists who specialize in that subject. As to whether L-arginine can be used to safely increase height in young people: The answer is that nobody knows.)
For most people, the doses of amino acids mentioned above (2 grams of L-glutamine and 10-30 grams of L-arginine) are about right for maintaining youthful levels of HGH beginning at about age 30, and continuing into the early 40s, and sometimes (but very rarely) beyond 50. In order to maintain its effectiveness, these amino acids should be used for about 6 weeks, then stopped for 2 or 3 weeks. The same 6-week ON, 2 or 3 weeks OFF cycle can be continued indefinitely. This cycling helps to maintain the effectiveness of the HGH release.
Unfortunately, the effectiveness of HGH release with amino acids is highly variable from individual to individual. (I cannot emphasize this individual variability enough!) For some people, it is not a very effective means of HGH release for any long period of time. For a few (very few) rare individuals, it maintains its effectiveness until the age of 60 and beyond.
For these amino acids to be effective, certain other substances must be present, and other substances must not be present.
In order to insure that you have the proper co-factors for these amino acids to produce HGH, it is best to take the L-arginine in one of the commercial products formulated by Durk Pearson and Sandy Shaw to optimize HGH release. Several companies listed in the Recommended Reading and Resources chapter sell these products under the brand names such as Innerpower™. Another advantage of using the Inner Power formulation is that L-arginine tastes awful, and you have to take too much of it to be able to take it in capsules. So the only practical way to take L-arginine is to take it, along with the necessary co-factors, in a specially formulated drink mix.
(Some other options for growth hormone release with arginine-based supplements were discussed in the chapter on Arginine.)
In order for your body to naturally produce HGH, or to produce HGH in response to certain amino acids, the following things must NOT be present:
* Anti-cholinergic medicines. This includes most medicines that make you drowsy or dehydrated. The most common of these medicines are the antihistamines that make you drowsy, including Benadryl (or any other brand of diphenhydramine), Sominex, Nytol, Tylenol-PM, and Zyrtec. (Claritin, Clarinex and Allegra probably do not affect the HGH-releasing effect of amino acids or natural HGH release.)
* Alcohol, in any appreciable quantity, blunts the HGH-releasing effect of amino acids and also suppresses natural HGH release. An ounce or less of alcohol two or three hours before taking a HGH releaser will have little effect on HGH release, but using alcohol to get to sleep can dramatically suppress your natural HGH release during sleep.
* Eating protein or carbohydrate within 3 hours before (or one hour after) taking an amino-acid HGH releaser will significantly blunt the growth hormone release induced by these amino acids.
There are many commercial products that are advertised to promote HGH release. Many of them are simply extremely expensive versions of the amino acids known to cause HGH release. Some of these products do work, but often at an extremely inflated price. Most of these products (especially the heavily advertised ones) are simply very expensive scams. (I get a lot of email from people asking about the latest of the many scams, and saying that surely this product must work because the advertising says that it does.) As the U.S. Food and Drug Administration has made it more difficult to obtain real human growth hormone, the number of HGH scams has grown by an incredible amount. If you search for information on HGH on the internet, you will find hundreds of these frauds and scams.
Many products are currently being advertised as Oral HGH sprays. I don't see how these products can possibly work. They don't contain enough HGH to have any biological effect, and all of the scientific evidence indicates that the HGH molecule is far too large to be absorbed through the membranes of the mouth. If HGH is swallowed, it is destroyed in the digestive tract before it can be absorbed into the blood stream.
The advertising for nearly all of the so-called "oral HGH sprays" is clearly fraudulent. Most people have received junk email advertising these products. I looked at the web site referred to by one of these bulk email ads. The web site quotes data from a report on injectable HGH, a completely unrelated product. The web site quotes data on oral absorption from the Physicians Desk Reference, but if you look at that page of the referenced edition of the Physicians Desk Reference, you see that the absorption data is for a completely unrelated multivitamin product made by another company.
Many "oral HGH" products advertise their HGH levels in nanograms. Keep in mind that the average daily injectable dose of HGH (one unit) is 333,333 nanograms, whereas the advertised amount of HGH in "oral HGH sprays" is 600 to 2000 nanograms per day. Also, without refrigeration, more than 90 percent of the HGH in an ordinary liquid solution is lost every 24 hours.
The technology for getting a molecule as large as HGH to be absorbed through the membranes of the mouth or nose is a technology potentially worth billions of dollars. No company that develops such an advanced technology is going to use it on an over-the-counter product.
The technology used to make an inhalable form of insulin was originally developed for use with human growth hormone. Genentech spent about $4 million on the use of this technology for an inhalable version of growth hormone between 1986 and 1989, but decided not to spend additional money to take the technology to market. Other companies have been sporadically working on an inhalable version of growth hormone, but it is a very technologically difficult project. Don't expect an inhalable growth hormone to be on the market for several years.
The internet is filled with fraudulent HGH products. Most of them use advertising tactics similar to those listed above. Some of the advertising is even more incredible. I found one Australian company openly advertising a pill that, according to the label, contained 8 milligrams of recombinant human growth hormone in each pill. A bottle of these pill was claimed to contain 2160 units of recombinant human growth hormone. They were selling the product for less than 35 Australian dollars per bottle. In almost any country in the world, 2160 units of recombinant human growth hormone would be about the same value as a very nice new automobile.
Growth Hormone Releasing Hormone
The information here on growth hormone releasing hormone (GHRH) will only be of academic interest to most people, since consistently effective medicines analogous to GHRH are not yet available. That situation may change in the future, though.
An injectable GHRH product has been produced with recombinant DNA technology, and was once commonly available by prescription in the United States and many other countries. It was sold under the brand name Geref by Serono Labs. GHRH is a protein consisting of a chain of 44 amino acids. Geref consists of only a 29 amino acid fragment of the GHRH molecule, but it appears to have the same effect as the full GHRH molecule (at least, for most people for a short period of time). The generic name of Geref is sermorelin.
Geref (sermorelin) was withdrawn from the market for general use in November, 2002. From 2002 until 2008, Geref was available only for diagnostic use and in clinical trials. In mid-2007, a few compounding pharmacies made sermorelin available available at a reasonable price for general use by prescription. This sermorelin is no longer available from compounding pharmacies, though. Much of the sermorelin sold in the United States in recent years reportedly came from biotech companies in China, and was not necessarily identical to Geref.
Geref was totally withdrawn from the market in 2008, with the last sales from Serono occurring on September 30, 2008.
Other than the exception noted above, at adult doses, the cost of Geref has always been more than injectable HGH, and it has always been more difficult to obtain. Also, it didn't work for everyone. Some studies indicate that GHRH seems to work better when used in conjunction with L-arginine. If the release of HGH in pulses is important, the use of sermorelin with L-arginine may be superior to the use of HGH, but this varies greatly from individual to individual. The use of sermorelin for anything other than diagnostic use has been generally disappointing.
One problem with sermorelin, as well as many other GHRH analogs, is that they have a very short lifetime in the body, usually with a half-life of only minutes. (It appears that this half-life problem can be solved for some of these GHRH analogs by chemically combining them with polyethylene glycol, among other methods.)
Sermorelin is a much smaller molecule than HGH, and research has been done on a sermorelin nasal spray. Only 3 to 5 percent of sermorelin is absorbed in the nasal spray form, however. This makes a sermorelin nasal spray far too expensive, so sermorelin was only available in injectable form.
Theratechnologies of Canada has developed what appears to be a much better form of GHRH. Tesamorelin contains the same number of amino acids (44) as natural growth hormone releasing hormone, but it has been modified to last longer in the human body. It avoids the short half-life problem of sermorelin, and tesamorelin appears to be much more effective. It is awaiting FDA approval in the United States for HIV-related fat accumulation. It is also currently under investigation for the reduction of abdominal fat in otherwise normal adults with reduced levels of growth hormone. The tentative plan is to sell Tesamorelin under the brand name Egrifta.
Tesamorelin has produced many encouraging results, including a small improvement in glucose levels. Human growth hormone often produces a temporary increase in insulin resistance when it is first started, especially in high doses. Tesamorelin seems to have the opposite effect. The manufacturer of Tesamorelin completed an agreement in October, 2008 with the pharmaceutical company Serono for marketing Tesamorelin in the United States, and an official New Drug Application was filed with the FDA on June 1, 2009. Tesamorelin is awaiting FDA approval. It is impossible to know what decision the FDA will make, since FDA decisions are not always based on science, but a response to the New Drug Application is expected in the second quarter of 2010. (The response is currently scheduled for May 27.) It is not known what legal and distribution restrictions that the FDA may place on the "off-label" use of Tesamorelin.
Another long-acting analog of GHRH that looks very promising is CJC-1295, but that product is at least 3 years away from approval by government agencies. CJC-1295 maintains a much longer half-life in the human body by partially binding to albumin, a important protein that is prevalent in the human bloodstream.
As stated earlier, pharmaceutical companies have produced growth hormone releasing agents that have been shown to be very effective in reversing the decline in HGH production with age. The one that has consistently worked the best is MK-0677 (ibutamoren mesylate), which is very effective in restoring HGH release in middle-aged and "normally-aging" elderly individuals to the levels of much younger people. MK-0677 is an oral medicine that restores the release of HGH in the pulsatile fashion characteristic of HGH release in young people. Unfortunately, it was not very effective in restoring HGH in the frail elderly, which was its original target market. It appears, in fact, that any form of HGH supplementation in the very frail elderly, and in the critically-ill elderly, is actually quite harmful. Restoring HGH in "normally-aging" people is not a function that the Food and Drug Administration (FDA) considers to be a legitimate function of a medicine; therefore, Merck (the pharmaceutical company) stopped all further development of MK-0677. Other effective oral HGH releasers developed by the pharmaceutical companies have faced a similar fate for similar reasons.
A considerable amount of research has been done on HGH releasers by the pharmaceutical companies, and some very promising substances have been developed, but there is no sign that any of them will be on the market anytime soon. MK-0677 (ibutamoren mesylate) is a substance, though, that seems to be too good to go away. It still appears in successful clinical trials from time to time. It recently completed another successful medical test in normally aging adults, and is currently undergoing clinical trials for use in fibromyalgia.
In a free market, MK-0677 (ibutamoren mesylate) would likely have had a revolutionary impact on the health of most people over 40. In fact, it is possible that MK-0677 could have revolutionized health care, prevented great human suffering, and literally saved trillions of dollars in health care. Since a free market in pharmaceuticals does not exist, MK-0677 will probably remain a laboratory curiosity more many years.
The one way to enhance your HGH levels regardless of age, or other factors, is to use injectable HGH. For most people past the age of 40 years or so, (until tesamorelin becomes available) this is the only HGH option that will really work well. The use of injectable HGH has been a subject shrouded in mystery for most people. The rest of this chapter will describe some of the details about what using injectable HGH is really like. The cost had come down to around $250 a month in the 2000-2003 time period for most adult hormone replacement doses, but the price has been increasing each year during the past few years. The process is as simple as getting a prescription from your doctor and getting the prescription filled at a drugstore. Human growth hormone is a prescription medicine in the United States and Canada, but does not require a prescription in all countries. (Getting a prescription has become the difficult part, but it can be well worth the time and effort.)
What doctor should you go to, and what drugstore should you use?
Any licensed physician can prescribe HGH, but few are willing to do so. It is best to find a physician who is familiar with HGH, and who has other patients using it. As stated elsewhere in this manual, there are 3 excellent sources for locating a physician knowledgeable about the prevention of age-related conditions, and these three sources are also the best for finding a physician to prescribe HGH therapy. Those lists of physicians are at the following web sites:
The American College for Advancement in Medicine
Life Extension Foundation
The American Academy of Anti-Aging Medicine
Not all of the physicians on the above lists are familiar with HGH therapy, and most of the physicians in the United States are not comfortable prescribing it because of the potential legal problems, so ask before making an appointment.
Because of the news stories about athletes using excessive doses of HGH, and of bodybuilders who use high doses of HGH in an highly-experimental and medically-uncontrolled environment, governments at the state and federal levels in the U.S. have cracked down on many physicians who write too many HGH prescriptions. This has scared many physicians away from prescribing HGH for new patients and has made finding a physician much more difficult in the past two years. Lawmakers at all levels of government in the United States believe that it is more important to prevent athletes from cheating than it is to keep ordinary adults healthy and out of nursing homes.
In addition, a number of prominent and powerful individuals have attacked all forms of anti-aging medicine in recent years. If you would like to see the kind of future that these people want for you, visit a local nursing home. A nursing home for the elderly contains the largest concentration of severely growth-hormone-deficient people that you will find anywhere. If you want to see how ill-informed are the opponents of the use of HGH against age-related conditions, do your own research at the National Library of Medicine web site referenced just below.
Because of the confusing way that the laws are written regarding the use of HGH, there has been a debate during the past few years among various attorneys and physicians about whether it is legal to prescribe HGH as an anti-aging treatment in the U.S. Since the FDA does not regard aging as a disease, and since HGH does not seem to affect the fundamental cause of aging, it is probably not legal to prescribe HGH for the nebulous diagnosis of "aging." Prescribing HGH for specific symptoms (or clusters of symptoms) of aging is an entirely different matter. A very large body of scientific evidence exists that HGH is useful against various manifestations of aging. You will have more success getting a prescription for HGH if you have such symptoms. If you have reached middle age or later, and you have no more symptoms of aging than you did when you were 25, and if you have no genetic tendency to suffer any ill effects from aging, then you will probably have considerable difficulty in getting a prescription for HGH.
Many U.S. residents who really need HGH have go outside the United States to get a legitimate prescription from a doctor and have the prescription filled by a pharmacy in that country. Even if you have a legitimate prescription from a physician in another country, and you clearly have a medical need for HGH, there is no guarantee that U.S. customs will allow you to bring back your prescribed medication. This situation may change, though. The increasing oppressiveness of the FDA is causing a backlash against that agency. Many people within the FDA have differing interpretations of their own rules.
You can do your own research on published scientific studies, starting at the PubMed gateway to the National Library of Medicine web site at:
PubMed home
I strongly recommend that everyone who values their health get a basic education about medical science and learn to use the National Library of Medicine database.
There have not yet been any comprehensive summaries published on long-term clinical studies on the use of growth hormone replacement therapy in "normal" individuals. Long-term studies have been done comparing HGH-deficient adults who use growth hormone therapy with similar HGH-deficient adults who do not use HGH therapy.
Most of the earlier published results of longer studies in persons suffering from only age-related conditions have used bizarre dosing regimens for HGH. This was understandable in the early studies, when the proper dosage in humans was unknown. It does NOT make sense that so many clinical studies continued to use such large doses long after the proper dosing levels was known. Overdosing on any hormone will inevitably lead to adverse effects. Most people using HGH to replace declining levels of growth hormone use one unit per day or less.
There have been two large studies that have been recently completed which monitored the results of replacement doses of HGH in adults who had a severe deficiency. The KIMS study was originally the Kabi International Metabolic Study, but is now called the Pfizer International Metabolic Database. It was a study by Pfizer of the use of Genotropin which, by 2003, had accumulated 40,000 patient-years of data.
A 2003 summary of the study in a special issue of "The Endocrinologist," the newsletter of the Society for Endocrinology, stated about the KIMS study, "It has confirmed, thus far, GH replacement is not associated with an increased risk of de novo neoplasia or diabetes mellitus."
For those who don't understand medical-speak, "de novo neoplasia" means "new tumors."
So, in 40,000 patient-years of observation of growth hormone replacement in adults, they could find no evidence of HGH replacement therapy causing new tumors or diabetes. In reading through papers on these two studies published since 2003, I haven't seen any mention of any subsequent finding of increased incidence of cancer or diabetes.
The KIMS study has now accumulated 60,000 patient-years of study, including 14,000 patients from 31 countries. Preliminary results of that study were published in articles in a supplement to the November 1, 2009 issue of the "European Journal of Endocrinology". (See references near the bottom of this page.)
The KIMS study used sophisticated quality of life measurements, and showed that HGH produced a dramatic increase in quality of life in adults who were formerly growth hormone deficient.
There is a similar but smaller study that has so far only accumulated 10,000 patient-years of data called the HypoCCS study on the use of Humatrope, sponsored by Eli Lilly. That study also hasn't found any evidence of new cancers or other significant health problems, but that study did not end until September 2009, and the conclusions of the study won't be available until well after the end of the study.
Both the KIMS and HypoCCS studies are of adults who were SEVERELY deficient in growth hormone, and whose growth hormone levels were brought into the normal range. There is no reason at all, though, to believe that the same safety profile wouldn't apply to adults who are only MODERATELY deficient in growth hormone, and whose growth hormone levels are brought into the normal range.
HGH is tightly regulated by the FDA, but HGH is not a controlled substance on the federal level in the United States. It is a controlled substance in some states, though. As of the last time I checked, HGH was a controlled substance in Idaho, Oregon, Rhode Island and West Virginia. In addition, Colorado has arbitrarily "defined" HGH as an anabolic steroid, effectively making it a controlled substance in that state. Other states place some additional restrictions on it as well. If HGH is a controlled substance where you live, it can still be prescribed for you. It just means that there are additional record-keeping requirements for the physician and the pharmacy. It also means that the state may become especially suspicious of physicians who prescribe it too frequently. For patients, the main implication of living in a state where HGH is a controlled substance is that it there are likely to be severe legal penalties for anyone who possesses HGH without a prescription.
Since most physicians who will prescribe HGH are maintaining a very low profile, they are very difficult for most people to find. One additional very valuable source of information can be a local compounding pharmacy. Type the phrase "compounding pharmacy" and the name of your city (or a nearby city) into a search engine such as Google. Ask the compounding pharmacy for the name of a physician who prescribes human growth hormone or who prescribes other bio-identical hormones. There are a few large compounding pharmacies that distribute their prescriptions nationally, and even around the world. These large compounding pharmacies can often recommend doctors all over the country.
There are some very good physicians countries outside the United States, especially Mexico, who will prescribe HGH. It will be necessary to have the prescription filled by a pharmacy in that country. In many countries, HGH is available without a prescription, so you should be able to buy the HGH from any legitimate source in the country where you get the prescription from a physician, then you should be able to bring up to a 90-day supply with you when you re-enter the United States. With the current restrictions on HGH in the United States, you may not be allowed to bring HGH across the border unless you have a doctor's prescription; and even with a prescription, the medicine that you need may be confiscated by U.S. customs.
Your medicine is much less likely to be confiscated if it is an FDA-approved brand. You will nearly always be allowed to bring your HGH into the United States if you have a legitimate prescription from a physician and you are bringing in an FDA-approved brand. It is very useful if you also have a signed statement of medical need by a licensed physician in the United States.
Most of the physicians who prescribe any hormone for you will want to do a comprehensive physical examination on your first visit. You will find that this initial consultation is well worth the money. Ask about cost first, though. With many physicians who prescribe natural hormone replacement in the United States, this initial exam will cost about $200 plus the costs of routine blood tests. The typical cost is often much higher in the coastal population centers, especially in New York, Florida and California. (A few "high-end" anti-aging clinics will charge $1,500 or more for an initial exam. The more expensive clinics may also want you to buy HGH directly from them for a highly inflated price -- 4 or 5 times the price you would pay at your local drugstore.)
For preventive medicine, ACAM physicians are the most likely to offer excellent service at a very reasonable cost, although most ACAM physicians are not comfortable prescribing HGH unless you are an established patient and the physician is thoroughly familiar with your medical history and medical need.
The physician who prescribes HGH will probably want to measure your IGF-1 levels before prescribing HGH, and again a few months after you begin taking HGH. IGF-1 is an abbreviation for Insulin-like Growth Factor 1. It is also known as Somatomedin-C. IGF-1 is a marker for HGH. Since natural HGH is released in surges, and it has a very short lifetime in the body, it is not practical to measure your HGH levels directly. Much of the HGH is used by the body to produce IGF-1, which has a fairly long lifetime in the body. An IGF-1 test generally costs about $100.
If you want to get an idea of your own growth hormone levels before visiting a doctor, or especially if your own physician will not order such a test, you can request your own test through reliable independent services. If you are in the United States, one way to get an IGF-1 (somatomedin-C) test is to order a Somatomedin-C Frozen Growth Hormone Marker Blood Test from the Life Extension Foundation. This test is sold by the Life Extension Foundation, but is actually performed by Labcorp (which still uses the older name somatomedin-C for IGF-1). Labcorp has about 1600 offices all across the United States where a sample of your blood for the test can be drawn. Your test results are mailed to you a few days later. (You can check the Labcorp web site for the location of a Labcorp testing office near you.) Unless you have an unusual medical situation, such as a very strong family history of certain types of cancer, you will probably want your IGF-1 (somatomedin-C) to be in the upper half of the normal range. There are other independent services that do blood testing at your request.
It was once thought that the effects of HGH were due to only to IGF-1. We know that IGF-1 has important effects, but the advantages that one gains with HGH are often not proportional to the increase it causes in IGF-1 levels. Some people on HGH therapy have only a small increase in IGF-1 levels, yet have large positive results from using HGH.
In spite of what a few government officials may say, there is no one universal medically-accepted test for measuring growth hormone deficiency in adults. It requires the judgement of a physician based upon a number of factors, and such judgements are always controversial.
Which brand of HGH? The sharp reduction in the price of HGH during the 1990's was due to the fact that several companies began producing it. Since the beginning of 2004, however, prices at most pharmacies have jumped by more than 25 percent. The price is still going back up by a few percent per year. In the United States, injectable human growth hormone is available in the following brands:
* Humatrope (from Eli Lilly). This was the first brand of HGH to become widely available.
* Genotropin (from Pharmacia/Upjohn).
* Saizen (from Serono Laboratories).
* Norditropin (from Novo Nordisk)
* Nutropin (from Genentech)
Tev-Tropin is a brand of HGH that is manufactured in Israel and approved for sale by the FDA in the United States. A long and complicated patent dispute kept Tev-Tropin off the market for many years. The patent dispute was settled in 2004, and Tev-Tropin began to be sold in the United States shortly thereafter. Like the other forms of HGH now sold in the United States, Tev-Tropin is the 191-amino-acid hormone that is identical to natural human growth hormone.
Serono also makes two additional brands of HGH, Serostim and Zorbtive, for special uses in diseases that require high doses of HGH.
In addition to these brands, there are 3 FDA-approved "bio-generics," formally named "follow-on protein products" by the FDA.
Omnitrope, manufactured by the Sandoz division of Novartis, was approved by the FDA on May 31, 2006.
In most countries where Omnitrope is sold, the price has been about 25 percent less than the other brands. It has taken a long time for Omnitrope to begin to penetrate the U.S. market well, but it appears that situation is beginning to change. Some pharmacies now sell Omnitrope at prices considerably below other brands of HGH.
Valtropin, made by LG Life Sciences, was approved by the FDA on April 19, 2007. The approval of Valtropin was not announced through the normal FDA channels, and the pharmaceutical press did not find out about its approval until several months later. It is sold in Europe, but it has been very slow to appear on the U.S. market.
Accretropin, produced by Cangene, was approved by the FDA on January 23, 2008.
Nine pharmaceutical companies are now authorized to sell HGH by prescription in the United States. All of these brands contain real high-quality injectable HGH made with recombinant DNA technology. Each of the brands is a little different in the packaging and mode of delivery, though.
Originally, the HGH package consisted of two vials. One vial contained powdered freeze-dried HGH. The other vial contained sterile water with a bacteriostatic preservative. When the user was ready to begin using the contents of the package, a certain amount of the sterile water would be drawn out of the second vial (with a needle and syringe) and injected into the first vial to dissolve the powdered HGH. The solution would then be ready for injection. The unused portion would have to be kept refrigerated. The entire vial of dissolved HGH would have to be used within 2 or 3 weeks.
The HGH is dissolved by the patient because HGH powder is much more durable than dissolved HGH. The dissolved HGH is very susceptible to being attacked by bacteria and degraded by proteolytic enzymes. HGH is always normally refrigerated, but if HGH powder is is left at room temperature for a few hours, no harm is done as long as the room is not too warm. Recently, some brands have developed formulations that can be kept outside of a refrigerator for extended periods after being dissolved in liquid, as long as they don't get too warm. (Sterile powdered HGH can even be left in a cool room for days or weeks, but this is not a good idea.) After being dissolved in water, the un-refrigerated HGH solution ordinarily loses its much of its potency after a few hours, and becomes completely unusable in a day or two, especially if the room is warm. The HGH solution must be kept refrigerated (unless you have one of the newer formulations that state otherwise).
HGH is still often sold with the HGH powder separate from the sterile water, but there are now several more convenient options for the mixing process.
In the Genotropin Intra-Mix cartridge, the HGH powder and the sterile water are in separate compartments of the same cartridge. Turning a knob on the handle at one end of the cartridge (until it screws all the way in -- three turns) automatically mixes the HGH and the sterile water. Since there is no mixing needle exposed to the room air, better sterility is obtained, and the Intra-Mix cartridge is advertised to last 3 weeks after mixing. (In the past, most other brands were advertised to last only 2 weeks, but this situation is changing. The Norditropin Pen and the Genotropin Miniquick are both newer products with much longer lifetimes. Even the brands that are advertised to last only 2 weeks will last much longer if you are careful about refrigeration.)
Another nice thing about special devices such as the Genotropin Intra-Mix cartridge is that it is very expensive to counterfeit such packaging. Counterfeit medicines are always a potential problem, and the older conventional two-vial HGH package is very easy to counterfeit -- and very profitable for any counterfeiter. Counterfeit HGH has not been a big problem, but counterfeit HGH has appeared on the market on several occasions. The most recent counterfeiting problem was with Nutropin, but that was several years ago.
Genotropin Intra-Mix cartridges have the most concentrated solution of HGH. With the 5.8 mg. (17.4 unit) cartridge, one unit of HGH is only 0.06 cc. This is about two drops. (This can be a significant psychological advantage when you're first learning to inject HGH.)
Most HGH packages require you to inject the HGH using insulin syringes. (The same ones used by diabetics.) Usually, you will use the smallest size syringe. This is a 0.3 cc. syringe with an 8 mm. 31 gauge needle. This is a very short, very thin needle. The B-D Ultra-Fine II insulin syringe with the 31-gauge needle is far superior to the syringes with the 30-gauge needles that were the best available until rather recently.
Some HGH packages use a pen with a built-in needle. For those who wish to avoid needles completely, Saizen is available in the CoolClick cartridge which blasts the HGH through the skin in a very narrow jet. Buying Saizen with the CoolClick cartridge will increase the cost, though. Depending upon where they are purchased, both the Genotropin Miniquick and the Norditropin Pen may actually cost less than the more conventional packaging.
HGH is sometimes measured in international units, and sometimes measured in milligrams (mg).
3 International Units = 1 milligram
Different doctors have different recommendations for the amount of HGH you should inject. The dose may depend upon your age and overall health. It is best to start with a low dose, such as one-half unit per day, and work up from there. Most physicians recommend taking 1 unit per day, 4 to 7 days a week.
Adverse effects from injectable HGH therapy are very rare as long as the amount of HGH used averages 1 unit or less per day. Most physicians familiar with adult HGH replacement therapy believe that 1.5 units per day reaches the point of diminishing returns, and more than 2 units per day begins to put you at some risk of side effects. (The clinical studies that resulted in frequent side effects from HGH used much larger doses. In fact, all of the most frequently-quoted clinical studies have used doses that we now know are ridiculously high doses.) In general, side effects of HGH are very rare in doses of 1 unit per day or less and common in doses above 2 units per day.
When you increase or decrease your dosage, it is best to do it very slowly. Even at doses below 2 units per day, abrupt changes in dosage can cause temporary problems such as water retention and headache in some people.
Many people experience increases in blood glucose levels when starting HGH. This effect usually goes away with time, but there appears to be a definite advantage to taking the prescription medicine metformin along with HGH to keep glucose levels under control. (Also, there is evidence that metformin can slow the aging process at a more fundamental level than HGH.) Alpha-lipoic acid or R-lipoic acid, which are both similar nutritional supplements, can also help to keep blood glucose levels under control.
Blood tests for thyroid function should be performed about three months after starting HGH. Growth hormone restores the ability of the body to convert the thyroid hormone T4 to T3, which is the active form. For this reason, it may decrease the need for thyroid, especially T3 replacement, in individuals with hypothyroidism (underactive thyroid). On the other hand, a recent medical study reported that growth hormone may unmask a previously undiagnosed thyroid problem. When the rest of the body begins functioning better, an aging thyroid gland may require assistance in the form of thyroid hormone supplementation. So your thyroid requirements may go up or down. There is no way to know without testing.
Anyone on any kind of hormone replacement therapy needs careful medical monitoring and frequent blood tests.
Since the largest natural HGH release in healthy young people occurs shortly after the onset of sleep, most doctors originally suggested that HGH be injected just before bedtime. Some people (especially those between 40 and 65 years old) report better results taking the HGH in the morning (or at some other time of the day), and letting their pituitary gland supply the nighttime HGH dose.
Most people over the age of 65 or 70 have a very small natural production of HGH after sleep onset, so injecting HGH just before bedtime is probably best for these older people.
There appears to be a definite advantage to dividing the HGH into a few smaller injections taken throughout the day. The advantage is usually not a large one, though, and most people find this far too inconvenient.
For most people, convenience outweighs the small advantages of one dosing schedule over another. Most people inject their growth hormone once a day at whatever time is the most convenient.
HGH requires a somewhat larger dose in women to achieve the same effectiveness as in men. Exactly why this is true is not well understood. It is known that taking oral estrogen cuts the effectiveness of HGH in half as compared with transdermal estrogen. Women taking oral estrogen should consider switching to patches or gels. On the other hand, supplementary estradiol (a common natural estrogen) is known to greatly enhance the natural release of HGH, as well as the release of HGH in response to pharmaceutical HGH releasers such as GHRP-2 and hexarelin.
People who do not start HGH replacement until after the age of 70 may have to remain on a lower dosage than younger individuals in order to avoid adverse effects. Many people who do not begin HGH until after they are 70 should not go above about one-half unit per day. This will, of course, vary by individual.
There have been claims that supplemental HGH increases the risk for cancer. There are valid theoretical reasons for suspecting this since HGH promotes cell division, however HGH also increases the effectiveness of the human immune system, which should reduce the risk of cancer. Correlations have been found between IGF-1 levels and certain types of cancer, but correlation is not the same as causation. We don't know what caused what in these correlations between high IGF-1 levels and cancer. Actual experience with HGH at replacement doses contradicts the claim that HGH increases the risk for cancer. I have heard of two cases of persons who were diagnosed with cancer when they first started on HGH therapy, but in these cases the cancer was clearly a pre-existing condition. I have never heard of any adult on replacement doses of HGH at one unit per day (or less) for a year or more ever getting cancer. This fact is rather remarkable considering the fact that most adults using HGH are in an age range where cancer is a significant risk. If you know of any situation where a person taking HGH at doses of one unit (or less) per day for a continuous period of at least a year has ever gotten cancer, please email me if you can give me details of such a case of cancer ever actually occurring. (I've had this notice on this page for a very long time, and I haven't heard of such a case of cancer yet.)
As noted above, the KIMS study, which monitored more than 40,000 patient-years of HGH use at replacement levels, found no increased risk of cancer.
There have also been claims that HGH slightly shortens life span. Those claims were based on studies in laboratory animals. A careful study of IGF-1 bioactivity and survival rates in humans (referenced at the bottom of this page), contradicts this claim. According to that study, higher IGF-1 bioactivity is associated with longer survival in elderly men.
HGH can be purchased through almost any pharmacy. At your local pharmacy, though, the price is likely to be higher than necessary, and they probably don't keep it in stock. Most local pharmacies require at least a day or two to obtain it. For these reasons, many people prefer to use a mail order pharmacy unless they live near a specialty pharmacy that is familiar with human growth hormone.
For general reference, some typical prices for human growth hormone are given below. These prices are now outdated, but the price situation keeps changing too fast for accurate updates. Here are some prices for HGH that came from the walgreens.com web site on May 7, 2007:
The Humatrope price listed above is the price of each vial in packages of 12.
Keep in mind that the typical adult replacement dose of HGH is one unit injected 4 to 7 times a week. So the above quantities are roughly a 3 to 4 week supply. The walgreens.com prices are not necessarily those you would have paid at your local Walgreens pharmacy at that date, but they were probably very close. There are some much more economical options by mail order from legitimate United States pharmacies.
Many people prefer to buy HGH from the large compounding pharmacies that have a special knowledge of medicines which work against the manifestations of aging. Your local pharmacist is probably not very familiar with HGH at all. These large compounding pharmacies are very familiar with HGH and routinely ship it all over the country, and in some cases around the world.
Until early 2007, a few of the larger compounding pharmacies in the United States were buying HGH in bulk from FDA-registered facilities in other countries and re-packaging it under their own brand as a specially-compounded product according to a physician's instructions for a specific purpose. It was sold under the generic name somatropin. The compounded HGH product was being sold for as little as $11 per unit. The United States Food and Drug Administration (FDA) has since blocked the importation of the HGH bulk material for compounding, and has criminally prosecuted the owners of some of those pharmacies. FDA policy is an ever-changing target, especially as it concerns human growth hormone. The FDA changes its policies for no apparent good reason, and it is not required to give any plausible justification for its decisions. These ever-changing legal policies are the primary reason that the subject of human growth hormone seems so complicated to most people when they first read about it.
The large compounding pharmacies may continue to be the best places to buy physician-prescribed major-label human growth hormone just because of their increased familiarity with the product.
As of mid-2007, the best price that I knew of at a licensed pharmacy within the United States on any of the major-label brands of HGH was $268.04 for 5.8 mg. Genotropin cartridges at Drugstore.com (as of January 31, 2007), however they usually don't keep this item in stock. That price was $15.40 per unit for purchases of 3 or more cartridges. (I have seen lower prices listed on other pharmacy web sites on one or two occasions, but telephone calls revealed that the product was not actually available.) Even at Drugstore.com, their web site often shows a price that is out-of-date. Many of the larger compounding pharmacies in the United States have very good prices on one particular brand of HGH. There have been significant price increases at the beginning of each of the past few years. Omnitrope is now generally the lowest price brand within the United States.
As is the case with most pharmacies, most of the pharmacists at Drugstore.com are not very familiar with HGH. With all of the different brands of HGH and different packaging of each brand, it may take several phone calls between the pharmacist and your physician and you to get everything set up just right.
One time that I ordered Genotropin from Drugstore.com, I got the bare cartridges when I wanted the assembled Intra-Mix cartridges. I know of other people that have had this happen to them at other pharmacies. If (like me) you already have Intra-Mix cartridges, you can just unscrew the external Genotropin Mixer from the Intra-Mix cartridges and use them on the bare Genotropin cartridges. (This is a good reason for always saving a couple of your old empty Intra-Mix cartridges.) Otherwise, you'll have to get the Genotropin Mixer, which is an external plastic device that screws onto the bare Genotropin cartridges. The Genotropin Mixer is something that your pharmacy can obtain, but it may take several days and cause you a lot of lost time and inconvenience.
If you have your prescription for HGH filled by a pharmacy by mail order, you will always have an overnight shipping charge. This usually amounts to about $17 for up to a six-month supply shipped anywhere in the U.S. It makes sense to order a three to six month supply to minimize shipping costs. Most pharmacies also have discounts for larger purchases.
Of course, all of the above-listed prices are subject to change, and I have no affiliation with any of these pharmacies.
You can also buy HGH in Mexico. The prices are generally lower in Mexico, and HGH from Mexico can be an option worth looking into, especially if you're planning to travel to Mexico anyway. (You should be aware that if you live in a state where HGH is a controlled substance, it may be illegal for you to possess HGH that has not been purchased from a legitimate source by prescription.) If you are going to purchase HGH in Mexico, it is best to go to a legitimate physician in Mexico for an examination and prescription, then have the prescription filled at a pharmacy or legitimate authorized pharmaceutical sales agent recommended by the physician.
Canadian pharmacies are generally not a reasonable option for U. S. customers purchasing HGH since Canada places severe restrictions on the sale of HGH, but there can be exceptions to this. The price of HGH is substantially less in Canada than in the U.S.
HGH from China is available on the black market and "gray" markets in the United States. Although some HGH from China is pure, and there is at least one FDA-registered production facility in China, some brands of HGH from China are often contaminated with foreign proteins, which cause allergic reactions. Consistency of strength is also a problem with many brands from China. At the present time, I consider the direct purchase of any form of HGH from China to be very risky for individuals, both legally and medically. (The manufacturer of the most reliable brand of HGH made in China claims that a counterfeit version of its product is being sold in the United States, and that its product is otherwise unavailable in the U.S.)
For more information about the practical aspects of using HGH, and other hormones, the following book is one of the best available on the subject:
Elmer Cranton, M.D. Resetting the Clock: 5 Anti-Aging Hormones That Are Revolutionizing the Quality and Length of Life. (M. Evans and Co. 1997)
More excellent information can also be found at Dr. Cranton's web site. Dr. Cranton's web site also includes updates of the book mentioned above.
For a excellent moderated discussion forum for users of injectable HGH, see:
The Yahoo Rejuvenation Forum
For many people, the main problem with HGH is the difficulty in giving themselves a injection. When you see a physician for an HGH prescription, you will receive instruction on how to give yourself the HGH injection. Nearly everyone has some apprehension about it the first few times that they do it. If you are a needle phobic, it may seem out of the question. If you do have needle phobia, please see the Needle Phobia Page at this web site.
Needle phobia is a serious problem, but it is one that can be overcome. Needle phobia has always been a problem for me. Because I have been on an experimental Life Extension program for most of my life, I usually get a complete blood chemistry test every six months. I always have to take certain precautions (listed on the Needle Phobia Page) when getting blood drawn for these tests. I still pass out during a needle procedure once every few years.
After getting blood drawn for a baseline IGF-1 reading before starting HGH injections in 2001, I passed out because of carelessly standing up too fast afterward. As I was lying on the floor of the doctor's office returning to consciousness, I was thinking to myself that my plan for giving myself 5 injections a week was not getting off to a very good start. I did begin giving myself HGH injections two weeks later, though. Overcoming needle phobia is sometimes very difficult, but it can be done. For anyone seriously interested in preventive medicine, overcoming needle phobia has enormous benefits.
For additional information about natural methods of increasing HGH, especially for people who can't afford, or just don't want to use, HGH injections, see the article provided to Futurescience by the Life Extension Foundation about Natural Means of Increasing Human Growth Hormone.
A few additional references:
Morrhaye G., Kermani H., Legros J.J., Baron F., Beguin Y., Moutschen M., Cheynier R., Martens H.J., Geenen V., Impact of growth hormone (GH) deficiency and GH replacement upon thymus function in adult patients. PLoS One. 2009 May 22; Vol. 4, issue 5: e5668.
French R.A., Broussard S.R., Meier W.A., Minshall C., Arkins S., Zachary J.F., Dantzer R., Kelley K.W., Age-associated loss of bone marrow hematopoietic cells is reversed by GH and accompanies thymic reconstitution. Endocrinology. 2002 Feb; Vol. 143, issue 2, pp. 690-9.
Brugts M.P., Van den Beld A.W., Hofland L.J., van der Wansem K., van Koetsveld P.M., Frystyk J., Lamberts S.W., Janssen J.A. Low Circulating IGF-I Bioactivity in Elderly Men is associated with Increased Mortality Journal of Clinical Endocrinology and Metabolism. 2008 Jul., Vol. 93, issue 7: pp. 2515-22
Svensson, J. and Bengtsson, B. Safety aspects of GH replacement. European Journal of Endocrinology, 2009 Nov 1., Vol 161, Issue S1, S65-S74.
Thomas, J.D.J. and Monson, J.P. Adult GH deficiency throughout lifetime. European Journal of Endocrinology, 2009 Nov 1., Vol 161, Issue S1, S97-S106.
Koltowska-Häggström, M., Mattsson,A.F., and Shalet, S.M. Assessment of quality of life in adult patients with GH deficiency: KIMS contribution to clinical practice and pharmacoeconomic evaluations. European Journal of Endocrinology, 2009 Nov 1., Vol 161, Issue S1, S51-S64.
An excellent technical book on HGH for scientists and health care professionals:
GROWTH HORMONE IN ADULTS: Physiological and Clinical Aspects, edited by Anders Juul and Jens O. L. Jorgensen. Cambridge University Press: 2000. (Very highly recommended)
I will be adding more scientific references as soon as I have the time. There are so many studies on HGH replacement, with the great majority showing positive results, that a detailed list of references would have to be put into a separate chapter.
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