Pharmacopsychiatry 2005; 38(5): 223-225
DOI: 10.1055/s-2005-873159
Letter
© Georg Thieme Verlag KG Stuttgart · New York

Risperidone Half-Life in a Patient Taking Paroxetine

A Case ReportJ. Barnhill1 , M. T. Susce1 , F. J. Diaz2 , J. de Leon1
  • 1University of Kentucky, Mental Health Research Center at Eastern State Hospital, Lexington, KY, USA
  • 2Department of Statistics, Universidad Nacional, Medellin, Colombia
Further Information

Publication History

Received: 29.3.2005 Revised: 29.5.2005

Accepted: 10.6.2005

Publication Date:
27 September 2005 (online)

This case report further establishes the inhibitory effects of paroxetine on risperidone (R) metabolism in a patient whose R was discontinued due to side effects. Baseline through levels in ng/ml were 33 for R, 9 for 9-hydroxyrisperidone (9-OHR) and 42 for the total moiety. The fourth morning after R discontinuation, levels were 4 for R, 1 for 9-OHR and 5 for the total moiety. The estimated half-lives were 23.8 hours for R, 22.8 hours for 9-OHR and 23.5 hours for the total moiety.

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Jose de Leon, M.D.

Mental Health Research Center at Eastern State Hospital

627 West Fourth St.

Lexington

KY 40508, USA

Phone: +1 859 2467487

Fax: +1 859 246 7019

Email: jdeleon@uky.edu