system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following is true of propylthiouracil?
assistant
The correct answer is  Ans. is 'd' i.e., It blocks thyroxine synthesis o Propylthiouracil blocks thyroxine synthesis by inhibiting thyroid peroxidase, and preventing oxidation of iodide/ iodotyrosyl residues, there by Inhibit iodination of tyrosine residue in thyroglobulin. Inhibit coupling of MIT and DIT to form T3 & T4. o Propylthiouracil also inhibit the peripheral conversion of T4 to T3. About other options o It is a hypothyroid drug, cannot be used in myxedema (hypothyroidism). It has a sho VA - 1-2 hours. It does not increase proteolysis of thyroxine.