What to know if you're vaccinated and want to donate blood and last updated 2021-05-17 08:23:56-04 GRAND RAPIDS, Mich. â If youâve been vaccinated, you can still donate blood but you do have to wait for two full days after your shot. Dr. Dan Waxman VP of Transfusion Medicine and Senior Medical Director at Versiti says the only reason for that is to make sure youâre not experiencing any side effects from the vaccine before you donate blood. âThere's nothing that a vaccinated donor could transmit to a patient,â says Waxman. Thatâs because the vaccines do not contain a live virus.