Thionamides are a class of drugs that are used to treat hyperthyroidism. The mechanism of action of thionamides is not fully understood, but it is thought to involve the inhibition of TPO-mediated coupling and the suppression of T cell-mediated immunity.
Thionamides also decreases the activity of type 1 deiodinase, which is responsible for the activation of T4 (that is its conversion to active thyroid hormone, T3). The result is a decrease in T3 levels and an increase in T4 levels. The net effect is a decrease in thyroid hormone production and an improvement in symptoms.
Mechanism of action of anti-thyroid drugs
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