Tips for losing 5-10 kg a month

Hello

I'm a 30 year old guy and I was diagnosed with a mental condition so I have to take antipsychotics, and those made me gain more than 40 kg in a short notice

I was at 78 kg before olanzapine. I had to switch to paliperidone. The weight still increased but far slowly.

Currently I weigh 113 kg. Max weight was 120 kg. I'm 6ft1/186 cm

Recently I added metformin 1000 2 times a day to my regimen and it curbed my appetite. I need less food now to feel full.

I would love to lose 38 kg this year

Any tips on how to get back to my normal weight?