What are the recommended dosages for medications used to treat tremor?

Recommended Dosages for Medications Used to Treat Tremor

For essential tremor, first-line treatments include propranolol (80-240 mg/day) and primidone (starting at 25 mg and titrating up to 150-250 mg/day), which can reduce tremor by approximately 50% in responsive patients. 1, 2

First-Line Medications for Essential Tremor

Beta-Blockers

• Propranolol: Start with 10-40 mg three times daily, with a maximum dosage of 120-320 mg/day 1, 3

  • Immediate release: 10-40 mg every 6 hours
  • Extended release: 60-160 mg every 12 hours 4
  • Acute adverse reactions occur in approximately 8% of patients 5
  • Contraindications include bradycardia, heart failure, asthma, and COPD 4

• Alternative Beta-Blockers (if propranolol not tolerated):

  • Metoprolol: 25-100 mg twice daily 4
  • Nadolol: 40-320 mg daily 4
  • Atenolol: 50-100 mg daily 1

Anticonvulsants

• Primidone: Start low at 25 mg at bedtime, gradually increase over 3 weeks to 150-250 mg/day 6, 5

  • Acute adverse reactions occur in approximately 32% of patients 5
  • Despite initial side effects, long-term tolerance is generally good 5
  • No significant difference in tolerability between tablet and suspension formulations 6

• Topiramate: Start at low dose and titrate up to 200-400 mg/day 2

• Gabapentin: Start at 100-300 mg at bedtime, increase to 900-3600 mg daily in divided doses 4

  • Dose increments of 50-100% every few days
  • Requires dose adjustment in renal insufficiency 4

Second-Line Medications

Benzodiazepines

• Clonazepam: Can be used for intermittent tremor during periods of stress or when first-line agents fail 1, 2
  • Caution regarding sedation, cognitive impairment, and potential for dependence

Other Anticonvulsants

• Pregabalin: Start at 50 mg three times daily, increase to 100 mg three times daily 4
  • Maximum dose: 600 mg/day in divided doses
  • Requires slower titration in elderly patients and those with renal insufficiency 4

Special Tremor Types

Head and Voice Tremor

• Botulinum toxin injections into affected muscles are recommended 1, 2
  • Dosing is individualized based on tremor severity and muscle involvement

Orthostatic Tremor

• Gabapentin: 900-3600 mg/day in divided doses 2
• Clonazepam: Typically 0.5-2 mg/day 2

Dystonic Tremor

• Anticholinergic medications may be beneficial 2
  • Trihexyphenidyl: Start at 1 mg daily, gradually increase to 6-15 mg/day

Practical Considerations

• A full therapeutic trial requires at least 4-8 weeks for most medications 4
• Increase dosage using increments of initial dose every 5-7 days until therapeutic benefits or significant side effects become apparent 4
• Approximately 50% of patients will respond adequately to medication therapy 1
• For patients with severe, medication-resistant tremor, surgical options (deep brain stimulation or thalamotomy) may provide 90% tremor control 1, 2

Common Pitfalls

• Underdosing is common in clinical practice; ensure adequate dosage trials before declaring treatment failure 1
• Starting primidone at too high a dose often leads to intolerable side effects; always start at low doses (25 mg) 6, 5
• Failure to recognize that combination therapy (propranolol plus primidone) may be more effective than monotherapy in refractory cases 1
• Not allowing sufficient time for therapeutic effect before changing medications 4