This is a breast cancer site.  I'm sorry but we can't really help provide you with the information you are looking for. Honestly your best bet is to consult with a doctor - considering that you have had heart surgery and other conditions to factor in.  But at 5'5" and 125, you're within your healthy range and shouldn't need diet aids.  From what I know - none of the above medications would cause you to "gain" weight - the amphetamine salts likely cause an accerlerated heart rate and your thyriod medicine should be ensuring that your thyroid is working right.  Also adderall is known for the side effects of weight loss, not gain.  I would recommend seeing your thyroid doctor and discussing the problem with him.  Likely that medicine is no longer working correctly. I hope that helps a bit. Angi