Infection In Injection Site

My friend sold some winnie to a friend of his and the guy was injecting into his glute, some how he got some type of infection and now they have to operate on his whole butt cheek, the guy might not have butt cheek soon, lol. How the hell could this have happened? I havent injected in my glute in a while, i usually do the traps, triceps or delts, but now im worried about shooting into the glute muscle.

My guess is cellolitus. Was there puss coming out of the infected site? Usually if there is and its inflamed, its cellulitos. What they do is cut open the infected area and squeeze the puss out. sucks, and hurts but thats how they did it in the military.

could have been an abscess, now they have to lance it. It can happen anywhere not just on the glute.