Amantadine weight gain

[MommaBsue]

Last year we tried amantadine with our son. It took the full 6 weeks for us to see any positive change. He has adhd, odd, anxiety disorder, and autism. The big change that we seen was he was hitting himself in the face less, he seemed calmer and was more responsible. The huge negative was that he had gained 15 pounds in that 6 weeks and he is already a bigger boy. We decided to try it again this year. He is 14 and was 118 lb when we started the medication. It has been almost 2 months and he is 137 lb. This is almost 20 lb in 2 months. I'm not sure the benefits completely outweigh the weight gain. Has anyone else had difficulty with weight gain on amantadine? Every study that I have read concludes that amantadine has helped with weight loss or weight maintenance without gaining weight from other antipsychotic medication. He is still taking Vyvanse as well.