Thrombocytopaenia: a serious side effect of diazoxide

Abstract

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.

Mind the Decimal Point: A Case of Diazoxide Overdose-Induced Ileus

“…We hypothesize the mechanism of ileus in patients receiving diazoxide may be secondary to retained fluid, as well as gastrointestinal smooth muscle relaxation, due to its mechanism of action on K-ATP channels. There are also various other more well-known side effects that may present with initiation of or during treatment with diazoxide, most notably edema, heart failure, pulmonary hypertension, ileus, necrotizing enterocolitis, diabetic ketoacidosis, hyperuricemia, thrombocytopenia, and neutropenia [3,7,[9][10][11][12]. The frequency at which patients experience edema while on diazoxide often leads to the concurrent initiation of diazoxide and a prophylactic diuretic [5].…”

“…Diazoxide stimulates the sulfonylurea receptor 1 subunit of adenosine triphosphate-sensitive potassium (K-ATP) channels on pancreatic beta cells, resulting in increased potassium efflux, cell hyperpolarization, reduced calcium influx, and thus suppression of calcium-mediated insulin secretion [5,7,8]. Potential adverse effects include edema, heart failure, pulmonary hypertension, ileus, necrotizing enterocolitis, vomiting, diabetic ketoacidosis, hyperuricemia, thrombocytopenia, and neutropenia [3,7,[9][10][11][12]. Overdose is infrequently reported [13].…”