CYTOMEL® (liothyronine sodium) tablets. DESCRIPTION. Thyroid hormone drugs are natural or synthetic preparations containing tetraiodothyronine (T4, levothyroxine) sodium or triiodothyronine (T3, liothyronine) sodium or both. For more information on managing weight with hypothyroidism read this article and this one. Summary: Both Armour Thyroid and Synthroid promote weight loss, which can help bring hormone levels back to normal. WARNING. Thyroid hormones, including SYNTHROID, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss. Medications like Thyroid, Cytomel, T3 and T4 are used to manage thyroid conditions, particularly an under-functioning thyroid. While they do cause weight loss, these drugs should not be used to help you lose weight if you have normal thyroid function. Synthroid (levothyroxine) treats hypothyroidism (low thyroid hormone) and different types of goiters (enlarged thyroid gland). Includes Synthroid side effects, interactions and indications. Sufficient levels of biotin are vital for hair, skin, and nails while low levels of the micronutrient can contribute to hair loss. Biotin deficiency is a rare nutritional disorder, especially in the countries where people consume enough food and calories. Along with its needed effects, levothyroxine (the active ingredient contained in Synthroid) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Cytomel (or other T3 medications) on the other hand do increase thyroid hormone in the body and thus can help boost metabolism and lead to weight loss. I was asked if I could provide a list of a drugs that can possibly trigger hair loss. I would like to start the list off with my current nemesis, Synthroid. I swear I've been on EVERYTHING except for Armour since my TT for cancer in Sept. '07. I started on a Levothyroxine and Cytomel combo and then switched to Synthroid only.