See Supplemental Patient Information
- Incidence of severe liver injury and acute liver failure, sometimes fatal, also requiring liver transplantation in adult and pediatric patients have been reported during propylthiouracil use [US Black Box Warning]
- Due to the increased risk of liver injury, propylthiouracil is not recommended for pediatric patients except in those who can not tolerate methimazole and when surgery or radioactive iodine therapy are not considered appropriate for the management of hyperthyroidism [US Black Box Warning]
- Cases of liver injury, including liver failure and death, have been reported in pregnant women (following first trimester) receiving this drug. It is advisable to use an alternative antithyroid drug after the first trimester of pregnancy
- Advise patients to inform any symptoms of hepatic dysfunction such as anorexia, pruritus, jaundice, dark urine, light colored stools, right upper quadrant pain, especially during the first 6 months of therapy. Discontinue therapy and perform LFTs, ALT and AST levels if these symptoms occur
- Therapy may cause fatal agranulocytosis including leukopenia, thrombocytopenia, and aplastic anemia (pancytopenia), typically during first 3 months of therapy; instruct patients to promptly report any symptoms suggestive of agranulocytosis including fever, sore throat, headache, or general malaise
- Discontinue therapy if agranulocytosis, aplastic anemia (pancytopenia), ANCA-positive vasculitis, hepatitis, interstitial pneumonitis, fever, or exfoliative dermatitis is suspected; also obtain the patient's bone marrow indices
- Monitor TSH and free T4 levels regularly with adjustments in dosing to maintain a euthyroid state because of the possibility of hypothyroidism during therapy
- Therapy may cause fetal goiter and cretinism when administered to a pregnant woman
- Monitor prothrombin time during therapy, particularly before surgical procedures, because propylthiouracil may cause hypoprothrombinemia and bleeding
Cautions: Use cautiously in
- Hepatic impairment
- Myelosuppression
- Concomitant drugs associated with agranulocytosis
- Elderly patients
Supplemental Patient Information
- Advise patients to promptly contact their physician if they become pregnant or intend to become pregnant while taking an antithyroid drug
Pregnancy Category:D
Breastfeeding: Propylthiouracil (PTU) had been considered the antithyroid drug of choice in nursing mothers; however, some experts now suggest methimazole to be the drug of choice during nursing owing to the higher rates of liver injury with PTU compared to methimazole. No cases of PTU-induced liver damage have been reported in breastfed infants. Discontinue the drug or stop breastfeeding if signs of liver toxicity occur. On usual maternal doses, very low amount of drug passes into breast milk, which is unlikely to cause infant thyroid suppression. Rarely, agranulocytosis or liver toxicity might occur; monitor infant's CBC with differential count and observe the infants for signs of infection and liver disease. This information is based upon LactMed database (available at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT last accessed 8 June 2011). As per manufacturer's data, the concentration of drug transferred to breast milk is very low and therefore likely results in clinically insignificant doses to the suckling infant.
US Trade Name(s)
US Availability
propylthiouracil (generic)
Canadian Trade Name(s)
Canadian Availability
Propyl-Thyracil
UK Trade Name(s)
UK Availability
propylthiouracil (generic)
Australian Trade Name(s)
Australian Availability
propylthiouracil (generic)
[Outline]
Pricing data from www.DrugStore.com in U.S.A.
- Propylthiouracil 50 MG TABS [Bottle] (WEST-WARD)
90 mg = $44.99
180 mg = $81.97
Warning: This pricing information is subject to change at the sole discretion of DS Pharmacy. For the most current and up-to-date pricing information, please visit drugstore.com.
