From
Endocrine Today:
The FDA has added a boxed warning to
propylthiouracil to include information on reports of severe liver injury and acute liver failure, of which some have been fatal, in both adult and pediatric patients.
Propylthiouracil is used to reduce thyroid hormone levels and to decrease symptoms associated with hyperthyroidism, but is not recommended for use in pediatric patients except in rare instances where other treatments are not appropriate.
The new warning states that, “for those being started on treatment for hyperthyroidism, it may be appropriate to reserve use of propylthiouracil for those who cannot tolerate other treatments such as methimazole, radioactive iodine or surgery.” However, propylthiouracil may be the treatment of choice before and during the first trimester of pregnancy due to the occurrence of birth defects observed with methimazole (Tapazole, King Pharmaceuticals).
In addition, the FDA is requiring that a Medication Guide be issued to patients filling a prescription for propylthiouracil, as part of a Risk Evaluation and Mitigation Strategy.
Both the boxed warning recommendations and the medication guide requirement are based on the FDA’s postmarketing review of safety reports in addition to meetings with the American Thyroid Association, the National Institute of Child Health and Human Development, and the pediatric endocrine clinical community.