Can You Donate Blood if You Smoke Weed? Mango Cannabis Marijuana and blood donation what you need to remember? If you use cannabis, do it safely Harvard Health Cannabis + Diabetes: What You Should Know Beyond Type 1 Yes, you can donate blood if you smoke or consume cannabis. The recipient of the blood will not get high, another common MYTH. All donors go through the same health Smoking (or vaping) doesn't affect your ability to donate blood. Help us bust this myth by sharing our post.