How is essential tremor typically managed?

Management of Essential Tremor

Essential tremor should be managed with propranolol or primidone as first-line pharmacological treatments when symptoms interfere with quality of life, followed by second-line medications if needed, and surgical interventions such as MRgFUS thalamotomy or deep brain stimulation for medication-refractory cases. 1, 2

Initial Assessment and Treatment Decision

• Essential tremor is the most common movement disorder after restless leg syndrome, with prevalence in the US estimated between 0.3% and 5.55% 2
• Treatment should only be initiated when tremor interferes with function or quality of life 2, 1
• The arms are the most commonly affected body part and cause the most functional disability 3

Pharmacological Management

First-Line Medications

• Propranolol and primidone are first-line treatments, effective in up to 70% of patients 1, 2
• These medications can be used alone or in combination if monotherapy is inadequate 3, 4
• Propranolol is the most established medication for essential tremor, having been used for over 40 years 1

Second-Line Medications

• If first-line agents fail, consider second-line options:
  • Gabapentin 1, 3
  • Topiramate 1, 3, 4
  • Other beta-blockers (atenolol, metoprolol) if propranolol causes adverse effects 3, 4
  • Benzodiazepines (e.g., clonazepam), particularly in patients with associated anxiety 3, 4

Treatment Limitations and Considerations

• Currently available medications improve tremor in only approximately 50% of patients 3, 4
• Beta-blockers should be avoided in patients with chronic obstructive pulmonary disease, bradycardia, or congestive heart failure 1
• Common side effects of beta-blockers include lethargy, depression, dizziness, hypotension, and exercise intolerance 1
• For patients with both essential tremor and hypertension, beta-blockers may provide dual benefits 1

Surgical Management for Medication-Refractory Tremor

Magnetic Resonance-Guided Focused Ultrasound (MRgFUS)

• Indicated for patients who have:
  1. Confirmed diagnosis of essential tremor
  2. Failed at least 2 medications (including 1 first-line medication)
  3. Appendicular tremor that interferes with quality of life 2
• MRgFUS provides sustained tremor improvement of 56% at 2-4 years 2, 1
• Contraindications include:
  • Need for bilateral treatment
  • Previous thalamotomy on the contralateral side
  • Inability to undergo MRI
  • Skull density ratio <0.40 2

Deep Brain Stimulation (DBS)

• DBS of the thalamic ventral intermediate nucleus is the current standard for severe medication-refractory tremor 5
• Provides adequate tremor control in approximately 90% of patients 3
• Preferred over thalamotomy for bilateral procedures to avoid adverse effects 3

Comparative Safety

• MRgFUS thalamotomy has a lower complication rate at 1 year (4.4%) compared to radiofrequency thalamotomy (11.8%) and DBS (21.1%) 2
• MRgFUS avoids risks of open surgery such as infection and hemorrhage 2

Other Treatment Options

• Botulinum toxin injections may be effective for head and voice tremor 3, 6
• Botulinum toxin for hand tremor is less commonly used due to risk of hand weakness 3
• Occupational therapy, speech therapy, and coping strategies may help manage mild to moderate tremor 5

Treatment Algorithm

1. Confirm diagnosis of essential tremor
2. Assess if tremor interferes with function or quality of life
3. If yes, start with first-line medication (propranolol or primidone)
4. If inadequate response, try the alternative first-line agent or combination therapy
5. If still inadequate, try second-line medications (gabapentin, topiramate, etc.)
6. For medication-refractory disabling tremor, consider surgical options:
   • MRgFUS thalamotomy for unilateral treatment in appropriate candidates
   • DBS for bilateral treatment or when MRgFUS is contraindicated 2, 5, 3

Monitoring

• Regular assessment of tremor severity and medication side effects is essential 1
• Dose adjustments may be needed based on clinical response and tolerability 1