CBD Cannabis and voluntary blood donations: what is the rule? Justbob Cannabis Use and Blood Donation: Unmasking the Truth Can Marijuana Use Prevent You From Giving Blood? Are vape pens, or e cigarettes, ever the better option? Ohio State Health & Discovery We all know smoking and vaping isn't great for your health. But it doesn't stop you from being a blood or plasma donor. Just make sure to wait one hour after donating Smoking (or vaping) doesn't affect your ability to donate blood. Help us bust this myth by sharing our post.