There are many combos of medications available.

What other ones have you tried ? what side effects?

Lamictal is a mood stabilizer but it mainly works on the depressive end of Bipolar
Latuda is also marketed for the depressive side.
Effexor "usually" brings people up.
Nexium decreases the acid in your stomach , but it can efect the way your medications are absorbed.

Have you been on a mood stabilizer in the past? Lithium, etc?

As for your weight it could be an issue , But I am anorexic and low weight but when I was on meds my body processed the meds very quickly so I had to take larger than average doses for them to work.

Did your pdoc start you on one medication at a time? If not you wont know what is helping or isn't and what is causing what side effect .

When I stopped my meds , It took me literally 3 months for my brain to return to working med free. So even if say the half life of a medication is 14 days ( just an example) you need 14 days after the last dose to be truly "off the med" then allow time for your body to respond without the daily dose of that Chemical.

Of course I am NO doctor , no one can diagnose but you will find everyone willing to share advice and there own expieirences

Welcome to PC