This definitely happened to me. I was on trileptal and something else and I did well for awhile, so I dropped everything I was on because I figured I didn't really need meds. Did well for six months and then started to cycle again. Tried trileptal again and nope, didn't work at all. Even after going higher on the dose. The seroquel didn't help either.

So yeah. I learned my lesson. I've been doing well now for eight months but I'm not going to take my chances going off my meds. Took me three years to find the right ones.