How to manage medication-induced tremors?

Management of Medication-Induced Tremors

The first step in managing medication-induced tremors is immediate discontinuation of the offending agent, as withdrawal of the causative drug is the primary treatment and should be done whenever drug-induced tremors are suspected. 1

Immediate Actions

• Identify and stop the offending medication immediately after excluding other arrhythmogenic or neurological substrates 1
• Common culprits include antiarrhythmics (amiodarone, procainamide), antipsychotics, SSRIs, lithium, valproate, stimulants, and beta-agonists 1
• For drug-induced cerebellar tremor (such as from high-dose cytarabine), immediate discontinuation is recommended rather than using tremor-specific medications 2
• Correct any electrolyte abnormalities (particularly potassium >4 mM/L and magnesium) and ensure adequate oxygenation 1

Symptomatic Treatment While Discontinuing the Offending Agent

If tremor persists after drug withdrawal or if the causative medication cannot be stopped immediately:

First-Line Symptomatic Treatment

• Propranolol is the medication of choice for symptomatic tremor control, starting at 10-40 mg every 6 hours (immediate release) or 60-160 mg every 12 hours (extended release) 3, 4, 5
• Contraindications include bradycardia, heart failure, asthma, and COPD 3
• Alternative beta-blockers (metoprolol 25-100 mg twice daily, nadolol 40-320 mg daily, or atenolol) can be used if propranolol is not tolerated 3, 4

Second-Line Options

• Gabapentin can be started at 100-300 mg at bedtime and increased to 900-3600 mg daily in divided doses, with dose increments of 50-100% every few days; requires dose adjustment in renal insufficiency 3
• Clonazepam for intermittent tremor during periods of stress, though caution is needed regarding sedation, cognitive impairment, and dependence potential 3
• Pregabalin starting at 50 mg three times daily, increased to 100 mg three times daily (maximum 600 mg/day), with slower titration in elderly patients 3

Special Considerations by Drug Class

Antiarrhythmic-Induced Tremor

• Amiodarone commonly causes tremor, ataxia, and peripheral neuropathy 1
• Mexiletine can cause tremor and ataxia 1
• Flecainide may cause tremor and vision disturbances 1

SSRI-Induced Tremor

• SSRIs (fluoxetine, paroxetine, sertraline, citalopram) can cause tremors, jitteriness, and hypertonia 1
• Signs typically appear within hours to days and may persist 1-4 weeks after discontinuation 1

Digitalis-Induced Tremor

• Manage with continuous cardiac monitoring, withdrawal of digitalis, and restoration of normal electrolytes (potassium >4 mM/L) 1
• Antidigitalis antibody is recommended for severe toxicity with sustained arrhythmias 1

Treatment Duration and Monitoring

• Allow at least 4-8 weeks for a full therapeutic trial of any symptomatic medication before changing agents 3
• Increase dosages using increments of the initial dose every 5-7 days until therapeutic benefits or significant side effects appear 3
• Recovery from drug-induced tremor is variable and may range from complete remission to persistent symptoms, particularly with cerebellar syndromes 2

Important Caveats

• Do not use calcium channel blockers (verapamil, diltiazem) for tremor management, as they can worsen certain conditions and are contraindicated in patients with myocardial dysfunction 1
• Avoid combining multiple CNS-active medications that could worsen tremor or cause drug-drug interactions 1
• In patients with renal or hepatic impairment, adjust doses accordingly and avoid medications with active metabolites that accumulate 1, 3
• Beta-blockers may mask hypoglycemia symptoms in diabetic patients and should be used cautiously 1