Dear user, I read carefully your problem and can understud your concern. Can you tell me please in which dose you are taking Synthroid ? May I know the last thyroid hormone levels? You are concern about your weight, mood chanches and hair loss.These are hypothyroid symptoms, that’s why iam asking you for TSH level? Synthroid (levothyroxin) is typically used to treat hypothyroid, and also for people with hypothyroid who often require lifelong thyroid hormone therapy. My advise in your case is to to the blood test for thyroid hormone : -TSH,FT3,FT4 -Tg You must be carefull because are some foods that can interefere with absorption of levothyroxin.(Soy products, calcium and irion supplememts which must to taken within four hours of levothyroxine.Grapefruit juice ,Don’t cosumetatit o lot of cup of coffe, because may interfere with the intestinal absorption of levothroxine) Tell your doctor please if you are taking other medicine:like antacids, cholestyramine ore ketamine and etc) If Synthroid can reduce thyroid level , my answered is Yes but please check thyroid hormone level.to prescriptation the right dose. Let us know your Synthroid dose . My sugest is to take the Synthroid with empty stomach at the same time each day . After the blood test for thyroid level please contacted with your endocrinologes for further suggestion. If you have any further queries, please feel free to ask. I would be happy to help. Kind Regards Dr KLodiana Poshi