acne treatment

When I checked on his scalp, the husband has bumps on it that we think are caused by acne. Not only that, his back has a few bumps too which he says are sensitive to the touch. He said it is acne. How does he know? Because he has had this on and off for years. He even had to take medications at one time because it got so bad on his face. Now acne is growing in his scalp and back. We think he needs back acne treatment but we wonder if this kind works for his scalp too? I am not very sure if he should use anything on his scalp for fear of hair falling but he will have to make a call on that. The back is safe enough to rub something on it should he decide to go the cream or liquid solution route. We do hope the acne will go away without medication. I think we are both too old to have acne but we somehow get it every now and then. I wonder if stress has something to do with it?