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Updated: Aug 1, 2025
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High-throughput Identification of Synergistic Drug Combinations by the Overlap2 Method
Published on: May 21, 2018
11.9K
Rifampin - Risperidone and Divalproex Drug-drug Interaction: A Case Report
Seo-Young Park1, Young-Min Park1
1Department of Psychiatry, Inje University Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Korea.
Summary
Rifampin, used for tuberculosis, can significantly reduce psychiatric medication effectiveness. This case highlights how rifampin-induced drug interactions impacted bipolar disorder treatment, necessitating medication adjustments for clinical improvement.
Area of Science:
- Pharmacology
- Psychiatry
- Infectious Disease
Background:
- Rifampin is a potent inducer of hepatic cytochrome enzymes, significantly affecting the metabolism of numerous drugs.
- Drug interactions involving rifampin can complicate the management of patients with comorbid psychiatric conditions.
Observation:
- A patient with bipolar disorder experienced persistent manic symptoms despite adequate divalproex dosage, likely due to concurrent rifampin therapy.
- The patient was treated with divalproex, risperidone, quetiapine, and clonazepam alongside anti-tuberculosis drugs including rifampin.
Findings:
- Serum valproate levels remained subtherapeutic (<2 μg/ml) despite a 900 mg/day divalproex dose, indicating rifampin-induced metabolism.
- Replacing risperidone with olanzapine led to rapid improvement in manic symptoms, suggesting rifampin's significant impact on risperidone levels and efficacy.
Implications:
- Clinicians must consider potential drug interactions when prescribing rifampin to psychiatric patients, particularly those on antipsychotics and mood stabilizers.
- Awareness of rifampin's potent enzyme-inducing properties is crucial for optimizing psychiatric treatment outcomes and preventing therapeutic failures.
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