PTU (generic: propylthiouracil) is a presciption medication used to treat hyperthyroidism (overactive thyroid), a condition in which the thyroid gland produces too much thyroid hormone. It is a synthetic hormone used to replace hormone normally produced by the thyroid to regulate energy and metabolism.

This medication comes in tablet form. It is taken 3 times daily, with or without food.

Common side effects of PTU include nausea, vomiting, and headache. PTU can cause drowsiness. Do not drive or operate heavy machinery until you know how this medication affects you.