Does 20mg amitriptyline cause weight gain?

I have been taking 20mg amitriptyline for three months for depression and insomnia. My sleep was better. But i gained weight ,i am not sure if it is because of amitriptyline. Last week i decided to reduce it. I take 10mg every day, but i started to sleep bad. What shall i do? Will i sleep better again or should i increase it again?
Thank you

I’ve taken 10, 25, 50 and now on 75mg for a decade and it hasn’t caused any weight gain. I have gained 5 kg in the last year but thats down to less exercise/moving and me eating more food/junk junk. Besides the 5kg since March 2023 to March 2024 I’ve maintained the same weight. Only know for sure as I got weighed when I began Stemcell treatment in 2023 and had my 1 year check up in March 2024. Weighed each time so they could track it.