hg57

I wondered the same thing and it was pretty much answered here;

I'm glad you're thinking about donating! If you donate blood stem cells (which occurs 75% of the time) you receive 5 days of an injection of something that boosts your stem cell count. I have talked to people that have received the injections and donated and they said they felt kind of crappy from them. But they could still go to work/school/do normal activities. After donating, you shouldn't have any side effects besides possibly a temporary bruise at the needle site (happens sometimes when you give blood) and maybe some fatigue. But that goes away and your stem cells regenerate in a few weeks so you're not giving away anything permanently. And you are only asked to donate if found to be a DNA match for a patient, which is super rare.