I can understand why you would be concerned about your brother. I am not a professional psychiatrist, so I can't diagnose. But I have Bipolar II and his behaviors sound in keeping with a bipolar diagnosis.

Alas, people respond in different ways to medicines and what works for one person doesn't work well for another. It sounds like the docs are still having to work to get his moods stabilized. They need to find the right drugs and the right levels of those drugs. It's a process of trial and error.

At least they know something he should not take. And now they need to get him off of that and work with other drugs.

I know it's upsetting seeing him this way, but it sounds like to me that the docs are on the right track and at some point he will be more stable with his moods and emotions. It just takes time.