Hi Nelly, Welcome to Heathcare Magic Physician s Desk! Thyroxine if taken in higher doses for long may be a cause for emotional lability and palpitation. You should get a morning empty stomach sample of Thyroid functions and lipid profile. Today s antidepressants are an array of great drugs, you may have side effects to one class but might be totally comfortable and happy with the other so give them a more chance with different version. Wish you a great health!