I’m going to be coming off of mirtazapine (anti depressant) in the next couple weeks and switching to a low dose of Quetiapine/Seroquel (antipsychotic)

I wanted to know what people’s experiences have been with the medication and any side effects that they’ve experienced. 

I know it’s shallow of me to be concerned about weight gain, but I’d rather be a sad skinny legend than a happy fat person so specifically wanted to know whether the weight gain is inevitable or if it’s purely an increase in appetite. 

Like will I feel hungrier so eat more or gain weight consuming the same amount of food that I currently do? 

(Please tell me the weight gain is avoidable)