a new medication

I've known my signficant other for 11 years since we were teenagers and is bipolar. As a person, he is kind, helpful, highly creative, intelligent, and loving. The disease part often alters who he is - into someone I don't know. It is a very difficult disease to have and to be around.. My love hasn't changed. Many people don't understand this disease. In the last year, we started living together. In the last three weeks, my significant has left (as this is common.) The medical staff aren't very helpful. I have just begun to searching for answers. Has anyone tried the new Serenity pill? How is it different from the Lithium.