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CASE REPORT
Serotonin syndrome induced by the combined use of metaxalone, phentermine, and duloxetine: A case report
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1
Department of Psychiatry and Behavioral Neurosciences, University of South Florida Morsani College of Medicine, Tampa, Florida,
United States of America
2
Department of Psychiatry and Behavioral Neurosciences, University of South Florida Morsani College of Medicine, Tampa,
Florida
3
Mental Health and Behavioral Sciences Service, James A. Haley Veterans Hospital, Tampa, Florida,
United States of America
JCBP, 4490 https://doi.org/10.36922/jcbp.4490
Submitted: 10 August 2024 | Accepted: 29 October 2024 | Published: 20 November 2024
© 2024 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Abstract
Serotonin syndrome is a potentially life-threatening condition caused by increased serotonergic activity. Although this condition is commonly associated with certain antidepressants, this report describes a case of serotonin syndrome induced by the combined use of metaxalone and phentermine with duloxetine and bupropion. Our patient developed serotonin syndrome following the administration of metaxalone for severe back spasms. Symptoms resolved following the discontinuation of these medications, provision of supportive care, and administration of lorazepam and cyproheptadine. This case report adds to the existing literature, as studies on metaxalone-induced serotonin syndrome are currently limited. This case report also highlights the importance of monitoring polypharmacy, especially when prescribing less common medications such as metaxalone as well as weight-loss medications such as phentermine.
Keywords
Serotonin syndrome
Serotonin toxicity
Metaxalone
Phentermine
Selective serotonin reuptake inhibitors
Polypharmacy
Funding
None.
Conflict of interest
The authors declare that they have no competing interests.
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