I have a friend that is injecting sustanon and deca into each arm (rear delt) and he keeps complaining that his arm hurts when he sleeps and works out... but it is only in his left arm. Is he doing it correctly or should he be injecting somewhere else?

How's that arm feeling, "friend"? STOP!! It's not worth it... read up on it dude... google steroid problems

Hi, RockyRock!

Is he under the guidance of a doctor for the injections, please?

Thanks!

If those steroids were not prescribed by a doctor, there is a good chance that they are not exactly what he thinks they are, and he risks an infection from something that may not be sterile. Or even steroids.

Is he cycling them?