title: Valproic acid-induced neutropenia.
abstract: OBJECTIVE
  To report a case of severe neutropenia caused by valproic acid (VPA).
  
  
  METHODS
  A 56-year-old white woman with an infectious brain abscess causing tonic-clonic seizure activity was treated with VPA. She developed severe neutropenia after 2 days of VPA therapy. The absolute neutrophil count reached a nadir of 47 cells/mm(3) during VPA use and returned to normal upon its discontinuation.
  
  
  CONCLUSIONS
  VPA is considered to be a well-tolerated antiepileptic drug. While neutropenia has been reported, it has been mild and transient. This patient developed severe neutropenia during effective treatment with VPA, making her significantly susceptible to infection. The Naranjo probability scale indicates VPA as the probable cause of neutropenia in this case.
  
  
  CONCLUSIONS
  This report of severe neutropenia caused by VPA emphasizes the importance of monitoring complete blood cell counts during therapy with this agent.
authors.affiliation: Department of Pharmacy, Clinical and Administrative Sciences, College of Pharmacy, University of Oklahoma, Oklahoma City, OK 73190-5040, USA. Kimi-Vesta@ouhsc.edu
authors.forename: Kimi S
authors.initials: KS
authors.lastname: Vesta
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Medina
mesh_terms: D001772:Blood Cell Count / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008875:Middle Aged; D009503:Neutropenia / Q000139:chemically induced* / Q000175:diagnosis; D014635:Valproic Acid / Q000009:adverse effects*
chemical_list: D014635:Valproic Acid