Can trazodone (antidepressant) cause tremors?

Trazodone and Tremor: Clinical Evidence and Considerations

Yes, trazodone can cause tremor as an adverse effect, particularly when used at higher doses, in combination with other serotonergic medications, or in elderly patients. While not among the most common side effects, tremor has been documented in both clinical guidelines and case reports.

Evidence for Trazodone-Induced Tremor

FDA Label Evidence

According to the FDA drug label, tremors are specifically listed as an adverse reaction occurring in approximately 3-5% of patients taking trazodone compared to 1-4% in placebo groups 1. This makes tremor a recognized, though not extremely common, side effect of trazodone therapy.

Clinical Guidelines and Case Reports

• The American Academy of Pediatrics guidelines (2016) specifically mention tremor as one of the common adverse effects of atypical antipsychotics and other psychotropic medications, including trazodone 2
• A recent case report (2022) described trazodone-induced parkinsonism in a 78-year-old male, which included coarse tremors of the upper extremities as a prominent symptom 3
• Another case report documented myoclonus (rhythmic tremor-like movements) secondary to concurrent use of trazodone and fluoxetine 4

Mechanisms of Trazodone-Induced Tremor

Trazodone-induced tremor may occur through several mechanisms:

1. Serotonergic effects: As a serotonin antagonist and reuptake inhibitor, trazodone can alter serotonin levels, which may affect motor control pathways 3

2. Drug interactions: When combined with other serotonergic medications, the risk of tremor increases significantly due to excessive serotonergic activity 4, 5

3. Serotonin syndrome: In severe cases, trazodone can contribute to serotonin syndrome, which includes tremor, myoclonus, hyperreflexia, and rigidity among its symptoms 5

Risk Factors for Trazodone-Induced Tremor

Several factors increase the risk of developing tremor while taking trazodone:

• Higher doses: Tremor risk appears to be dose-dependent
• Advanced age: Elderly patients are more susceptible to neurological side effects
• Polypharmacy: Concurrent use of other medications, particularly:
  • Other antidepressants (especially SSRIs)
  • Medications that inhibit CYP3A4 (which metabolizes trazodone)
  • Other serotonergic medications
• Pre-existing neurological conditions
• Renal or hepatic impairment: May lead to higher blood levels of trazodone

Clinical Management

For patients who develop tremor while taking trazodone:

1. Dose evaluation: Consider reducing the dose if clinically appropriate
2. Medication review: Assess for drug interactions that may be contributing to tremor
3. Discontinuation: If tremor is severe or significantly impacts quality of life, consider discontinuing trazodone - symptoms typically resolve within days to weeks after discontinuation 3
4. Alternative medications: Consider non-serotonergic alternatives for insomnia or depression treatment

Special Considerations

• Elderly patients: Use lower starting doses and monitor closely for neurological side effects
• Essential tremor: Interestingly, one older study suggested trazodone might actually improve essential tremor in some patients 6, though this is not a standard indication
• Parkinson-like symptoms: Be alert for the development of parkinsonian symptoms (rigidity, bradykinesia, tremor) which may indicate a more serious adverse effect 3

Prevention

To minimize the risk of tremor when prescribing trazodone:

• Start with low doses (25-50mg) and titrate slowly
• Avoid combining with multiple other serotonergic medications
• Educate patients about early signs of tremor and when to report them
• Consider alternative medications in patients with pre-existing movement disorders

Tremor from trazodone, while not the most common side effect, is a recognized adverse reaction that clinicians should monitor for, particularly in high-risk patients or those on multiple medications.