Thrombocytopaenia: a serious side effect of diazoxide

BMJ Case Rep. 2019 Sep 11;12(9):e231222. doi: 10.1136/bcr-2019-231222.


A 2.5-year-old boy with a history of (transient) congenital hyperinsulinism was admitted to the paediatric ward with recurrent hypoglycaemia. Diazoxide 5 mg/kg/day and hydrochlorothiazide 2 mg/kg/day were initiated. After increasing the dose of diazoxide to 10 mg/kg/day, the child developed mild rectal bleeding, petechiae, epistaxis and haematemesis. Blood screening showed severe thrombocytopaenia. Diazoxide and hydrochlorothiazide were stopped, and his platelet count normalised. Drug rechallenge was positive. Drug-induced immune thrombocytopaenia was diagnosed.

Keywords: Endocrinology; Haematology (incl Blood Transfusion); Paediatrics; Pharmacology And Therapeutics.

Publication types

  • Case Reports

MeSH terms

  • Antihypertensive Agents / adverse effects*
  • Child, Preschool
  • Diazoxide / adverse effects*
  • Drug Therapy, Combination / adverse effects
  • Epistaxis / chemically induced
  • Hematemesis / chemically induced
  • Humans
  • Hydrochlorothiazide / adverse effects*
  • Hyperinsulinism / congenital
  • Hyperinsulinism / drug therapy
  • Male
  • Rectal Diseases / chemically induced
  • Thrombocytopenia / chemically induced*


  • Antihypertensive Agents
  • Hydrochlorothiazide
  • Diazoxide