propylthiouracil /prō′pilthī″əyo͝or″əsil/ , an inhibitor of thyroid hormone biosynthesis. ▪ INDICATIONS: It is prescribed in treatment of hyperthyroidism and thyrotoxic crisis and in preparation for thyroidectomy. ▪ CONTRAINDICATIONS: Mental depression, cold intolerance, or known hypersensitivity to this drug prohibits its use. Caution is recommended in pregnancy, in patients older than 40 years of age (can cause hypoprothrombinemia and bleeding), and in use in combination with other drugs that can cause agranulocytosis. ▪ ADVERSE EFFECTS: Among the more serious adverse effects are GI distress, pruritus, and rashes. Rarely blood dyscrasia occurs.
