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Weight decline in patients switching from olanzapine to quetiapine

Sanjay Gupta1, Prakash S Masand, Shubdeep Virk

  • 1Department of Psychiatry, University of Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA. sgupta1@adelphia.net

Schizophrenia Research
|July 13, 2004
PubMed

Insights

Switching from olanzapine to quetiapine helped patients lose weight without impacting psychiatric efficacy or safety. This strategy offers a potential solution for managing significant weight gain associated with olanzapine treatment.

Area of Science:

  • Psychiatry
  • Pharmacology

Background:

  • Olanzapine is associated with significant weight gain, impacting patient adherence and metabolic health.
  • Managing antipsychotic-induced weight gain is crucial for long-term treatment success.

Purpose of the Study:

  • To evaluate the efficacy and safety of switching from olanzapine to quetiapine in patients with excessive weight gain.
  • To assess changes in weight, psychiatric symptoms, extrapyramidal side effects, and metabolic parameters.

Main Methods:

  • An open-label, 10-week study involving 16 patients psychiatrically stable on olanzapine but with >20% weight gain.
  • Patients were switched to quetiapine over 4 weeks, with subsequent 6-week follow-up.
  • Assessments included weight, Positive and Negative Symptom Syndrome Scale (PANSS), Simpson-Angus Scale (SAS), and metabolic labs.

Main Results:

  • A mean weight loss of 2.25 kg was observed (P = 0.03).
  • No significant changes were noted in PANSS scores, SAS scores, or metabolic parameters.
  • 12 out of 16 patients completed the study, indicating good tolerability.

Conclusions:

  • Switching from olanzapine to quetiapine is a viable strategy for managing olanzapine-induced weight gain.
  • This approach appears safe and does not compromise antipsychotic efficacy or metabolic stability in the short term.
  • Further research with larger, controlled trials is recommended to confirm these findings.

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