Sodium Valproate (Epilim Chrono - I specify because apparently they can have slightly different effects!)
It's working really well, no sleepiness (opposed to Seroquel which was a bit of a nightmare.)
My pdoc said it is usually more effective for people who rapid cycle or have more irregular mood swings in general and/or irritability. I would definitely recommend talking about it with your pdoc, although there is a severe down side of not being allowed to get pregnant while on it as it can cause severe problems to the child.

Ohh...And I have already put on weight It's been only a month though, ask me a bit later and I'll let you know if this side effect went away as it is supposed to do or not