Blood Donation Eligibility from the Massachusetts General Hospital website
You can donate whole blood if you:
Are in good health and feel well
Weigh at least 110 pounds and at most 350 lbs
Have eaten recently
Have a photo ID
Haven't donated in 56 days
Antibiotics: Donors are deferred for 24 hours after their final dose.
Cancer: Donors with a history of most types of cancer are eligible to donate 5 years from the date of their last treatment.
Exceptions There is no deferral period for donors with a history of: Basal cell carcinoma of the skin Squamous cell carcinoma of the skin Carcinoma-in-situ or Dysplasia of the cervix or breast, if treated There is a permanent deferral for donors with a history of: Waldenstrom's Macroglobulinemia
Colds: Donors are not eligible if they are not feeling well and healthy the day of donation.
Diabetes: Donors with diabetes (type I or II) are eligible to donate.
Dental Work: Donors are eligible to donate following routine dental work.
Gonorrhea: Donor is deferred for 12 months after date of last treatment.
Heart Attack: Further evaluation is needed.
High Blood Pressure: Donors with high blood pressure are eligible to donate if their blood pressure is controlled with medication.
Pregnant: Donors who are pregnant or less than six weeks postpartum are not eligible to donate.
Stitches: Donors are not eligible while stitches/sutures are still in.
Transfusion: Donor is deferred for 12 months after a transfusion of blood or blood components.
Transplant: Donor is deferred for 12 months after an organ transplant.
Individuals who have had a positive test for HIV/AIDS or who have been at risk for contracting HIV/AIDS are permanently deferred from blood donation.
Malarial-Endemic Areas: Donor is deferred for 12 months after travel to a malarial-endemic area.
United Kingdom: Donor is permanently deferred for travel/residence of 3 months or more in the United Kingdom (England, Northern Ireland, Scotland Wales, The Isle of Man, or the Channel Islands) from 1980-1996.
Europe: Donor is permanently deferred for travel/residence of 5 years or more in Europe since 1980. There are some exceptions regarding military bases.
Other Lifestyle Factors
Ear/Body Piercing: Donor is eligible if piercing was performed using sterile single-use equipment.
Tattoos: Donor is deferred for 12 months after getting a tattoo
All information from the MGH website.