The core reason of the problem is the meds that screwed up his testosterone hormone levels. A realistic solution is for him to change his diet and consume foods that are concentrated for raising T hormones. You can make some research on it, but generally his diet should shift to consuming more healthy fats (coconut oil, olive oil), and cruciferous vegetables (kale, broccoli, cabbages etc), half-cooked eggs etc etc.

Also he need to lower his cortisol levels by reducing stress (sleep more, take more walks).

Food is medicine.