Kneepads is right you can donate Plasma while on gear , they test the plasma for desies and such drugs like opiates.
You won't looses any gains if you donate , the process take the plasma out of you blood and replaces it with glucose based saline
then the put it back into you body , you get a cold feeling throughout your body due to the fact that the solution they put back in you is colder than your blood , this is the only side effect that I've seen
My fiance used to work for Nabi Bio Medical which is a plasma donation center (called something else now) and I used to get to go donate all the time , their are a few people out their that have a special platelet in their blood that makes it extra special , and they pay alot more for your plasma , like 40$ a visitand you can donate like 3 times a week so that would almost pay for a GH cycle !!!!