title: Toxicological considerations for antithyroid drugs in children.
abstract: BACKGROUND
  Propylthiouracil (PTU), methimazole (MMI) and carbimazole are indicated for the treatment of hyperthyroidism in adult and pediatric patients. The aim of this review is to present all the relevant information regarding the use of antithyroid drugs (ATD) in pediatric thyrotoxic cases, the pediatric toxicology of ATD and the warning which has recently been issued for PTU by the FDA.
  
  
  METHODS
  Epidemiology, diagnosis and treatment of pediatric thyrotoxicosis are all presented in this article. The authors also extensively discuss the details regarding the pharmacology, bioactivation, biodisposition, bioavailability and pharmacokinetic properties of the two main ATD (MMI and PTU).
  
  
  CONCLUSIONS
  The FDA recently reported that use of PTU is associated with a higher risk for clinically serious or fatal liver injury compared to MMI in both adult and pediatric patients. They also found that congenital malformations were reported approximately three times more often with prenatal exposure to MMI compared with PTU and especially with the use of MMI during the first trimester of pregnancy. The authors believe that PTU should not be used in pediatric patients unless the patient is allergic to or intolerant of MMI, and there are no other treatment options available. That being said, PTU may be the treatment of choice during, and just before, the first trimester of pregnancy.
authors.affiliation: Panagia General Hospital, Department of Endocrinology, Diabetes and Metabolism, N. Plastira, 22, N. Krini 55132, Thessaloniki, Greece.
authors.forename: Spiros
authors.initials: S
authors.lastname: Karras
authors.forename: Themistoklis
authors.initials: T
authors.lastname: Tzotzas
authors.forename: Gerasimos E
authors.initials: GE
authors.lastname: Krassas
mesh_terms: D000380:Agranulocytosis / Q000150:complications; D000818:Animals; D013956:Antithyroid Agents / Q000627:therapeutic use / Q000633:toxicity*; D002231:Carbimazole / Q000627:therapeutic use / Q000633:toxicity*; D002648:Child; D002675:Child, Preschool; D019317:Evidence-Based Medicine; D005260:Female; D006111:Graves Disease / Q000188:drug therapy; D006801:Humans; D006980:Hyperthyroidism / Q000188:drug therapy; D017093:Liver Failure / Q000150:complications; D008713:Methimazole / Q000627:therapeutic use / Q000633:toxicity*; D011247:Pregnancy; D011441:Propylthiouracil / Q000627:therapeutic use / Q000633:toxicity*; D016032:Randomized Controlled Trials as Topic; D013971:Thyrotoxicosis / Q000188:drug therapy; D014657:Vasculitis / Q000150:complications
chemical_list: D013956:Antithyroid Agents; D008713:Methimazole; D011441:Propylthiouracil; D002231:Carbimazole