His medications may be the reason for his new behavior, but it may also be that his new behavior comes from his condition. Sometimes a person acts more outgoing to hide their stresses. I've known people who partied just to forget or hide their problems. This is, however, not very sustainable. Eventually it gets too expensive and unhealthy.
One might argue that meds and treatment also get too expensive and/or unhealthy, but there are at least assistance programs for these.

I would interpret that your friend saw his lifestyle, whatever it was, as taking a toll.
Trying to push him in a direction away from whatever is making him feel more comfortable now will likely cause a backlash.