Mechanism of action of propylthiouracilin hypehyroidism is:: (A) Inhibition of organification of iodine, (B) Inhibition of oxidation of iodine, (C) Inhibition of coupling of two DIT residues, (D) All of the above
Answer is D. (Ref: KDT 6/e p248) Propylthiouracil, carbimazole and methimazole act by inhibiting the enzyme, thyroid peroxidase. It catalyses: Oxidation of iodine Organification Coupling