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It depends on how high your hematocrit is. If it's really over the normal range then aspirin won't be enough. I got severe headaches even with borderline high hematocrit.
I don't see why you can't give blood but if you don't qualify for donating they can either use only a fraction of your blood like platelets so donation requirements are much less stringent, or even destroy and throw away your blood. You could even buy a kit online and ask a student nurse to do that for you at a medical school as part of their required practices.
It might be better if you donate/have blood withdrawn right after the labs, so you'll have almost 3 mos for your body to recover for the next labs.
Just don't risk a stroke because of high hematocrit.
I don't see why you can't give blood but if you don't qualify for donating they can either use only a fraction of your blood like platelets so donation requirements are much less stringent, or even destroy and throw away your blood. You could even buy a kit online and ask a student nurse to do that for you at a medical school as part of their required practices.
It might be better if you donate/have blood withdrawn right after the labs, so you'll have almost 3 mos for your body to recover for the next labs.
Just don't risk a stroke because of high hematocrit.