Propylthiouracil inhibits the synthesis of thyroid hormones and thus is effective in the treatment of hyperthyroidism.

Propylthiouracil is indicated for:

• Graves’ disease or toxic multinodular goiter in patients intolerant of methimazole and unfit for surgery or radioactive iodine.

• Symptomatic relief prior to thyroidectomy or radioactive iodine therapy in such patients.

Adults:

• Initial: 300 mg/day in 3 divided doses.
• Maintenance: 100–150 mg/day.
• Severe cases: up to 600–900 mg/day.

Pediatrics (rare use only):

• Start at 50 mg/day, titrate carefully.

Liver failure

Agranulocytosis, aplastic anemia

Vasculitis

Stevens-Johnson syndrome

Nausea, vomiting, joint/muscle pain

Loss of taste or hair

Headache, dizziness, rash

Hypersensitivity to propylthiouracil or any of its components.

Liver Toxicity

Agranulocytosis

Vasculitis

Pregnancy

Monitor for liver symptoms (e.g., pruritus, RUQ pain, jaundice).

Evaluate for blood disorders, especially if signs of infection or general malaise occur.

Drug interactions: enhances effects of warfarin, affects beta-blockers, digitalis, and theophylline.

May cause hypoprothrombinemia, requiring prothrombin time monitoring, especially before surgery.