Cytomel T-4

levothyroxine sodium

Cytomel T-4 (Levothyroxine) is a synthetic version of the principle thyroid hormone, thyroxine (T4) that is made and released by the thyroid gland. Thyroid hormone increases the metabolic rate of cells of all tissues in the body. In the fetus and newborn, thyroid hormone is important for the growth and development of all tissues including bones and the brain. In adults, thyroid hormone helps to maintain brain function, food metabolism, and body temperature, among other effects.

Cytomel causes a faster conversion of carbohydrates, proteins and fats. Bodybuilders are especially interested in an increased lipolysis, which means increased fat burning. Competing bodybuilders use Cytomel during the weeks before a championship since it helps to maintain an extremely low fat content, without necessitating a hunger diet. Athletes who use low dosages of Cytomel report that by the simultaneous intake of steroids, the steroids become more effective, most likely as the result of the faster conversion of protein.

Cytomel T-4 is the less powerful of the two most popular thyroid replacement drugs on the market. If you have naturally low T3 levels, then you may be able to supplement with T4, and have it convert to T3 via your body’s natural metabolic pathways, which involves the deiodinase enzyme. However, there have been a number of studies that have shown that during reduced caloric intake, and/or when carbohydrate intake is reduced dramatically, levels of deiodinase decline, hindering the conversion of T4 to the physiologically active T3.

As compared to Cytomel T-3, Cytomel T-4 requires significantly higher doses to be effective. However, the combination of both works best.

Effective dosage
Effective dosage rang from 100 mcg/day to up to 300 mcg/day. It is administered as a single daily dose, preferably one-half to one-hour before breakfast with a full glass of water.

Side effects
Levothyroxine therapy is usually well-tolerated. If symptoms occur, often they are due to toxic levels of thyroid hormone and the symptoms are those of hyperthyroidism. Symptoms may include all or some of the following: chest pain, increased heart rate or pulse rate, excessive sweating, heat intolerance, nervousness, headache, insomnia, diarrhea, vomiting, weight loss, or fever. Women may experience irregular menstrual cycles.