Northern Pharmaceuticals Synthroid T4 (Sodium Levothyroxine), is a synthetic form of the thyroid hormone T4. It regulates the metabolism in protiens, fats and carbohydrates; increases the oxygen supply to tissue as well as assists in decreasing body fat in the body. If caloric intake is higher the individual can substantially deacrease body fat at the same time. The prooduct has also shown to exert an anabolic effect while being used. Recommended dose can be anywhere between 100mcg - 300mcg per day.