Trazodone-induced parkinsonism: A case report.

Area of Science:

• Geriatric Medicine
• Pharmacology
• Neurology

Background:

• Trazodone is frequently prescribed off-label for insomnia in older adults.
• At low doses, trazodone acts as a histamine-1 (H1) receptor antagonist, producing a hypnotic effect.
• Potential severe side effects include suicidal behavior, excessive sedation, QT prolongation, and priapism.

Observation:

• A 78-year-old male with multiple comorbidities developed tremors, rigidity, and gait disturbance after starting trazodone for insomnia.
• The patient presented with coarse tremors, difficulty writing, and a shuffling gait with foot-dragging.
• Clinical examination revealed bilateral cogwheel rigidity and an unsteady gait, indicative of parkinsonism.

Findings:

• Trazodone was identified as the likely cause of parkinsonism in this patient.
• Concurrent amiodarone use may have impaired trazodone metabolism, potentially increasing its blood levels.
• The serotonin-dopamine system interaction is a significant proposed mechanism for trazodone-induced parkinsonism.

Implications:

• This case underscores the importance of considering trazodone-induced parkinsonism, especially in elderly patients with polypharmacy.
• Physicians must carefully weigh the benefits against the potential risks of trazodone and other medications in older adults.
• Polypharmacy can exacerbate drug adverse effects, necessitating vigilant monitoring and medication review in geriatric patients.