Yes, there is bc involved here.
I should have been more specific. Coumarin, hydroxyethylrutosides, diosmin and hesperidin are all flavonoids -- they are natural supplements, not pharmecuticals (actually, hydroxyethylrutosides are a derivative of rutin, which is a derivative of buckwheat, so it's not exactly natural, but it is considered an herbal supp, much like ala).
I already harvest dandelion leaves (add the leaves right to your green leaf salad!) (it's the leaves that potentiate the water retention, they are high in potassium; the root structure is used more for constipation), however, dandelion is thought to be far less effective than the above-mentioned compounds. Hence, my interest.
Some info that got me interested:
Edema:
Several double-blind trials2 3 4 5 have found that 400 mg per day of coumarin, a flavonoid found in a variety of herbs, can improve many types of edema, including lymphedema after surgery. However, a large double-blind trial detected no benefit using 200 mg coumarin twice daily for six months in women who had arm edema after mastectomy (surgical breast removal).6 (Coumarin should not be confused with the anticlotting drug Coumadin®.)
A group of semi-synthetic flavonoids, known as hydroxyethylrutosides, are also beneficial for some types of edema.7 One double-blind trial found that 2 grams per day of hydroxyethylrutosides reduced ankle and foot edema in people with venous disorders after four weeks.8 Another double-blind trial found that 3 grams per day of hydroxyethylrutosides significantly reduced lymphedema of the arm or leg and lessened the associated uncomfortable symptoms.9
A combination of the flavonoids diosmin (900 mg per day) and hesperidin (100 mg per day) has been investigated for the treatment of a variety of venous circulation disorders.10 However, in a double-blind trial, this combination was not effective for lymphedema caused by breast cancer treatments.11
Some info on other herbals:
Herbs that stimulate the kidneys were traditionally used to reduce edema. Herbal diuretics do not work the same way that drugs do, thus it is unclear whether such herbs would be effective for this purpose. Goldenrod (Solidago cnadensis) is considered one of the strongest herbal diuretics.15 Animal studies show, at very high amounts (2 grams per 2.2 pounds of body weight), that dandelion leaves possess diuretic effects that may be comparable to the prescription diuretic furosemide (Lasix®).16 Human clinical trials have not been completed to confirm these results. Corn silk (Zea mays) has also long been used as a diuretic, though a human study did not find that it increased urine output.17 Thus, diuretic herbs are not yet well supported for use in reducing edema.
2. Becker HM, Niedermaier G, Orend KH. Benzopyrone in the therapy of postreconstructive edema. A clinical double-blind study. Fortschr Med 1985;103:593–6 [in German].
3. Casley-Smith JR, Morgan RG, Piller NB. Treatment of lymphedema of the arms and legs with 5,6-benzo- [a]-pyrone. N Engl J Med 1993;329:1158–63.
4. Chang TS, Gan JL, Fu KD, Huang WY. The use of 5,6 benzo-[alpha]-pyrone (coumarin) and heating by microwaves in the treatment of chronic lymphedema of the legs. Lymphology 1996;29:106–11.
5. Casley-Smith JR, Wang CT, Casley-Smith JR, Zi-hai C. Treatment of filarial lymphoedema and elephantiasis with 5,6-benzo-alpha-pyrone (coumarin). BMJ 1993;307:1037–41.
6. Loprinzi CL, Kugler JW, Sloan JA, et al. Lack of effect of coumarin in women with lymphedema after treatment for breast cancer. N Engl J Med 1999;340:346–50.
7. Wadworth AN, Faulds D. Hydroxyethylrutosides. A review of its pharmacology, and therapeutic efficacy in venous insufficiency and related disorders. Drugs 1992;44:1013–32 [review].
8. Renton S, Leon M, Belcaro G, Nicolaides AN. The effect of hydroxyethylrutosides on capillary filtration in moderate venous hypertension: a double blind study. Int Angiol 1994;13:259–62.
9. Piller NB, Morgan RG, Casley-Smith JR. A double-blind cross over trial of o-beta-hydroxyethyl-rutosides (benzopyrones) in the treatment of lymphoedema of the arms and legs. Br J Plast Surg 1988;41:20–7.
10. Struckmann JR. Clinical efficacy of micronized purified flavonoid fraction: an overview. J Vasc Res 1999;36 Suppl 1:37–41 [review].
11. Pecking AP, Fevrier B, Wargon C, Pillion G. Efficacy of Daflon 500 mg in the treatment of lymphedema (secondary to conventional therapy of breast cancer). Angiology 1997;48:93–8.
15. Tyler V. Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York: Pharmaceutical Products Press, 1994, 74 [review].
16. Racz-Kotilla E, Racz G, Solomon A. The action of Taraxacum officinale extracts on the body weight and diuresis of laboratory animals. Planta Med 1974;26:212–7.
17. Doan DD, Nguyen NH, Doan HK, et al. Studies on the individual and combined diuretic effects of four Vietnamese traditional herbal remedies (Zea mays, Imperata cylindrica, Plantago major and Orthosiphon stamineus). J Ethnopharmacol 1994;36:225–31.
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