Hypothyroidism is a common disorder [1] whose diagnosis frequency has gradually risen. Although synthetic thyroxine (T4), L-triiodothyronine (T3), and T3/T4 combinations are available for correction of hypothyroidism, the treatment of choice is T4 alone for the vast majority of patients. The bioavailability of a drug depends on many factors such as drug disintegration and dissolution, time of drug intake, storage conditions, diet, and the tablet's size. The T4 is recommended to be taken as a single dose with a glass of water, preferably on an empty stomach, at least 0.5h to 1h before breakfast.
