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Pharmacopsychiatry 2009; 42(2): 61-65
DOI: 10.1055/s-0028-1102912
Original Paper

© Georg Thieme Verlag KG Stuttgart · New York

Confusion, a Rather Serious Adverse Drug Reaction with Valproic Acid: A Review of the French Pharmacovigilance Database

E. Bondon-Guitton 1 , A. Sommet 1 , 2 , J. L. Montastruc 1 , 2 and the French Association of Regional Pharmacovigilance Centres
  • 1Laboratoire de Pharmacologie Médicale et Clinique, Unité de Pharmacoépidémiologie, EA3696, Université de Toulouse, Faculté de Médecine, Toulouse, France
  • 2Service de Pharmacologie Clinique, Centre Midi-Pyrénées de Pharmacovigilance, de Pharmacoépidémiologie et d’Informations sur le Médicament, Centre Hospitalier Universitaire de Toulouse, Toulouse, France
Further Information

Publication History

received 14.03.2008 revised 18.07.2008

accepted 03.09.2008

Publication Date:
23 March 2009 (online)

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Abstract

Introduction: Confusion is an adverse drug reaction frequently observed with valproic acid. Some case reports are published in the literature but no systematic study from a sample of patients has been published. We performed this study in order to describe the main characteristics of this adverse drug reaction.

Methods: Using the French Pharmacovigilance database, we selected the cases of confusion reported since 1985 with valproic acid.

Results: 272 cases of confusion were reported with valproic acid: 153 women and 119 men. Confusion mostly occurred during the two first weeks following valproic acid exposure (39.7%). It was “serious” for almost 2/3 of the patients (62.5%) and its outcome favourable in most of the cases (82%). The occurrence of this ADR was more frequent in patients aged between 61 and 80 years.

Conclusion: This work shows that confusion with valproic acid is a serious, rather frequent but reversible adverse drug reaction. It occurs especially in older patients and during the first two weeks of treatment.

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Correspondence

E. Bondon-GuittonPharmD, PhD 

Laboratoire de Pharmacologie Médicale et Clinique

37 Allées Jules-Guesde

31000

Toulouse

France

Phone: +33/5/6114 59 18

Fax: +33/5/6125 51 16

Email: guitton@cict.fr