Why do you tie your weight loss to a lack of exercise? Were you doing muscle mass building exercise and diet?

Could it be you have a metabolic disorder or a psychiatric disorder that is driving the weight loss. I lost 38 pounds in 6 weeks 4 years ago due to a high stress event. My doc put me on Zyprexa for 6 weeks to stop the weight loss. I gained 12 pounds back to a healthy weight.

I recently lost 5 pounds due to the stress of moving. Exercise has never appeared to help me put weight on. Just the opposite.

There are changes the body goes through during adolescence that effect weight.

Weight is directly related to calorie intake. A rule of thumb is that a pound equals about 3500 calories. Eat 3500 calories less each week will cause a pound of weight loss per week. Raise metabolism with anxiety and those pounds can be lost without any change in diet.

To gain weight, one needs to consume an additional 3500 calories for each pound gained, even more if anxiety levels are increased.

Zonisamide has been used in treatment of obese adolescents (eg, Zonisamide for Weight Loss in Adolescents).

Perhaps you could talk to your prescribing doctor about whether another drug might meet your needs better.