kaeti, thank you very much!

"He was doped" means someone (or something) was given drugs. "His drink was doped" (there were drugs in the drink). Or "Only after she was doped did she get any sleep." It's a passive sentence (He was hit, She was fed) which usually means someone else was doing it (passive sentences mean the subject does not perform the action). So yes it was done to him/ it wasn't voluntary. "He doped" sounds strange because it isn't a complete sentence. "He used dope." or "He took dope." sound better. Or you can expand the sentence. "He doped before the race." "He doped from 2010-2019." I think "He used dope" sounds better than "He doped".