I had a major personality change a little over a year ago when I became suicidal. All my life until then I had been upbeat, laid back and loved life. I was diagnosed with clinical depression and given antidepressants to correct the chemical imbalance in my brain. Has your friend only seen a psychiatrist, or has he also been checked out by his regular dr. for this? Sometimes psychiatrists go a little overboard with their treatment of psychosis when what it really is is an imbalance (in this case brought on by the narcotics your friend was given) in his brain.