Can I donate blood if I smoked marijuana the day before the blood drive?

All blood collection facilities would treat marijuana use the same as alcohol: If donor staff can detect the smell of marijuana or alcohol, the person would not be allowed to donate at that time. This has nothing to do with intoxicants in the blood component; the amount present would have no effect on the patient. The alcohol or THC could, when combined with the loss of fluid volume and red cell mass, increase the risk of post-donation reactions such as dizziness, fainting, nausea, etc.

Yes. Marijuana does not stay in your blood stream, it's stored in your fat cells. Nobody will ever be able to tell that you smoked weed if you donate blood.

Absolutely, I used to do it all the time. There is a little waiver you have to sign that says you're "Drug free" but your THC doesn't hurt the blood, and they still accept it and you'll still save a life. I know I did :3

Yeah its alright,I did that before and once after a few beers

yeah you can long as you dont got hiv or hepatitis