If the anorexia nervosa has caused you to lose an excessive amount of weight, shouldn't a treatment for it be directed toward getting your weight back to normal? Unless your weight has moved above normal for your body mass index (BMI), I would consider the possibility that your concern for the weight gain is the anorexia nervosa talking to you, not the prozac.
Well, my question is really if it causes weight gain and abnormalities in metabolism.
Many people who take Prosac for a variety of reasons say they experience weight gain. My point is, it's a concern for someone who is overweight now but until you become overweight, it shouldn't be a concern for you. Talk to the person that prescribed the prosac about your concerns.
I just hope it doesn't continue to make me gain weight for no reason at all.