I try to rotate as many sites as possible, so I end up shooting traps, chest, shoulders, lats, triceps, biceps and quads.
Everything is always fine everywhere except biceps; Every time without fail they get red, warm and swollen a few days post injection.
I've heard some people say this is "normal" and to let the body deal with it on it's own, but I always get scared and end up taking antibiotics for a few days until they get better.
Does anyone have any idea what could cause this? I know the simple solution is to stop shooting biceps, but I'm really curious why this happens there and nowhere else.