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Dose-dependent impulse control disorders in piribedil overdose
Juan Carlos Giugni1, Lorena Tschopp, Victoria Escalante
1Hospital de Clínicas Ciudad Autónoma de Buenos Aires, Argentina.
Clinical Neuropharmacology
|January 14, 2012
Summary
High piribedil doses in Parkinson disease can trigger impulse control disorders (ICDs) and dopamine dysregulation syndrome (DDS). Reducing piribedil and increasing levodopa improved symptoms without worsening side effects.
Area of Science:
- Neurology
- Pharmacology
Background:
- Parkinson disease (PD) management often involves dopamine agonists.
- Impulse control disorders (ICDs) and dopamine dysregulation syndrome (DDS) are known potential side effects of dopaminergic therapy.
Observation:
- A 73-year-old female with PD experienced compulsive shopping and behavioral changes after inadvertently taking a higher dose of piribedil (400 mg/d).
- The patient exhibited symptoms consistent with ICDs and DDS, including excessive purchasing and nonsensical queries.
- Mild dyskinesia was noted during examination.
Findings:
- The patient was diagnosed with ICDs and likely DDS.
- Decreasing piribedil to 200 mg/d and increasing levodopa to 750 mg/d resolved the compulsive behaviors without exacerbating dyskinesia.
Implications:
- This case underscores that even seemingly well-tolerated dopamine agonist doses can induce adverse effects upon increment.
- Careful dose titration and monitoring are crucial in managing Parkinson disease to prevent psychiatric and behavioral complications.
- Understanding the dose-dependent risks of dopamine agonists is essential for optimizing patient outcomes in PD treatment.
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