9 weeks eh? I'm surprised you're still at 50mg, but I can imagine anti-depressants with Bipolar can make things more tricky.

I was up to 200mg at one point. It did help, but eventually it just wasn't doing it for me so I quit cold turkey (do not recommend).

Perhaps you could bring up the topic of an increased dose next time you see your psychiatrist? 50mg is on the low side. Good luck!