Severe psychotic exacerbation during combined treatment with aripiprazole/haloperidol after prior treatment with risperidone

Abstract

Objective. Aripiprazole is a new generation antipsychotic drug that shows a partial agonistic activity at D₂ and 5-HT_1A receptors. This might lead in some cases to an exacerbation of psychotic symptoms due to dopamine agonism. Methods. We report the case of a 39-year-old woman with an ICD-10 defined schizoaffective disorder. Results. Risperidone was started to treat psychotic symptoms. Psychotic symptoms disappeared but because of galactorrhoea risperidone needed to be discontinued. Subsequently, an antipsychotic treatment regimen with aripiprazole and haloperidol was prescribed. After initiating aripiprazole and haloperidol the patient's psychotic symptoms increased drastically. Therefore aripiprazole and haloperidol were discontinued. Olanzapine was prescribed and psychotic symptoms declined again. Conclusion. Concurrent causes for this serious adverse event may be the partial agonistic activity of aripiprazole at D₂ receptors as well as an up-regulation of dopamine receptors during prior treatment with risperidone. Both aspects may have contributed to the severe psychotic exacerbation. Clinicians should be aware of this possible, serious adverse event while switching to aripiprazole or prescribing aripiprazole with other antipsychotics. Because of their lower D₂ receptor affinity quetiapine and clozapine might be a better choice for combined treatment with aripiprazole.

Key Words::

• Adverse drug reaction
• psychosis
• aripiprazole
• pharmacodynamics
• schizoaffective disorder

Acknowledgements

None.

Statement of Interest

The AMSP Drug Safety Program is organized by non-profit associations in Germany, Austria and Switzerland. Almost all pharmaceutical companies involved in CNS research contribute financial support to the three associations:

Educational and research grants since 1993:

Austrian Companies: Astra Zeneca Österreich GmbH, Boehringer Ingelheim Austria, Bristol Myers Squibb GmbH, CSC Pharmaceuticals GmbH, Eli Lilly GmbH, Germania Pharma GmbH, GlaxoSmithKline Pharma GmbH, Janssen-Cilag Pharma GmbH, Lundbeck GmbH, Novartis Pharma GmbH, Pfizer Med Inform, Wyeth Lederle Pharma GmbH

German Companies: Abbott GmbH & Co. KG, AstraZeneca GmbH, Aventis Pharma Deutschland GmbH GE-O/R/N, Bayer Vital GmbH & Co. KG, Boehringer Mannheim GmbH, Bristol-Myers-Squibb, Ciba Geigy GmbH, Desitin Arzneimittel GmbH, Duphar Pharma GmbH & Co. KG, Eisai GmbH, esparma GmbH Arzneimittel, GlaxoSmithKline Pharma GmbH & Co. KG, Hoffmann-La Roche AG Medical Affairs, Janssen-Cilag GmbH, Janssen Research Foundation, Knoll Deutschland GmbH, Lilly Deutschland GmbH Niederlassung Bad Homburg, Lundbeck GmbH & Co. KG, Novartis Pharma GmbH, Nordmark Arzneimittel GmbH, Organon GmbH, Otsuka-Pharma Frankfurt, Pfizer GmbH, Pharmacia & Upjohn GmbH, Promonta Lundbeck Arzneimittel, Rhone-Poulenc Rohrer, Sanofi-Synthelabo GmbH, Sanofi-Aventis Deutschland, Schering AG, SmithKline Beecham Pharma GmbH, Solvay Arzneimittel GmbH, Synthelabo Arzneimittel GmbH, Dr. Wilmar Schwabe GmbH & Co., Thiemann Arzneimittel GmbH, Troponwerke GmbH & Co. KG, Upjohn GmbH, Wander Pharma GmbH, Wyeth-Pharma GmbH

Switzerland Companies: AHP (Schweiz) AG, AstraZeneca AG, Bristol-Myers Squibb AG, Desitin Pharma GmbH, Eli Lilly (Suisse) S.A., Essex Chemie AG, GlaxoSmithKline AG, Janssen-Cilag AG, Lundbeck (Suisse) AG, Organon AG, Pfizer AG, Pharmacia, Sanofi-Aventis (Suisse) S.A., Sanofi-Synthélabo SA, Servier SA, SmithKlineBeecham AG, Solvay Pharma AG, Wyeth AHP (Suisse) AG, Wyeth Pharmaceuticals AG

Dr Grohmann: is the project manager of AMSP. Dr Letmaier has received honoraria as a speaker from Bristol-Meyers Squibb, Eli Lilly and Lundbeck. The other authors declare no conflicts of interest.