title: Acute dapsone intoxication: a pediatric case report.
abstract: BACKGROUND
  There are many case reports of dapsone overdose in adults but only a few reports of dapsone-induced methemoglobinemia in children. We report a case of a three-year-old boy who developed prolonged recurrent methemoglobinemia following an ingestion of dapsone.
  
  
  METHODS
  Case report.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Not applicable.
  
  
  RESULTS
  This child developed significant symptoms of methemoglobinemia approximately two hours after ingesting dapsone 37.5 mg/kg. The initial methemoglobin level measured 2.5 hours after ingestion was 44%. The patient was treated with multiple doses of activated charcoal and methylene blue. Three doses of methylene blue reduced the methemoglobin level to 6% by approximately 16 hours after the overdose but the level rebounded to nearly 15% at 64 hours postingestion.
  
  
  CONCLUSIONS
  Dapsone is a drug that is being used for a wide variety of clinical conditions. The primary clinical manifestation of dapsone overdose is methemoglobinemia. An important aspect of dapsone poisoning is its ability to produce methemoglobinemia, which is long lasting and which may recur following methylene blue therapy. Because of this, dapsone-poisoned children need to be monitored for two to three days.
authors.affiliation: Department of Emergency Medicine, Queen's University-Kingston, Ontario, Canada.
authors.forename: R D
authors.initials: RD
authors.lastname: MacDonald
authors.forename: M A
authors.initials: MA
authors.lastname: McGuigan
mesh_terms: D000962:Antimalarials / Q000506:poisoning*; D002606:Charcoal / Q000627:therapeutic use; D002675:Child, Preschool; D003622:Dapsone / Q000506:poisoning*; D006801:Humans; D008297:Male; D008708:Methemoglobinemia / Q000139:chemically induced* / Q000628:therapy; D008751:Methylene Blue / Q000627:therapeutic use; D011041:Poisoning / Q000628:therapy; D012008:Recurrence
chemical_list: D000962:Antimalarials; D002606:Charcoal; D003622:Dapsone; D008751:Methylene Blue