Evaluation and Treatment Approach for Tremor
The evaluation of tremor should begin with a targeted history and physical examination to categorize the tremor by activation condition (rest vs. action), topographic distribution, and frequency, followed by appropriate diagnostic testing and treatment based on the identified tremor type. 1
Initial Evaluation
History
Tremor characteristics:
- Activation condition: Rest tremor (occurs when body part is relaxed) vs. action tremor (occurs with voluntary muscle contraction) 2
- Distribution: Unilateral vs. bilateral, affected body parts (hands, head, voice, etc.)
- Timing: Constant vs. intermittent, situation-specific triggers
- Progression: Sudden vs. gradual onset, stable vs. worsening
- Alleviating/exacerbating factors: Stress, caffeine, alcohol, certain positions
Associated symptoms:
- Parkinsonian features: Bradykinesia, rigidity, postural instability
- Cerebellar signs: Ataxia, dysmetria
- Neurological symptoms: Weakness, sensory changes, cognitive issues
Medication review:
- Current medications that may cause/exacerbate tremor (SSRIs, stimulants, lithium)
- Caffeine intake and alcohol use 3
Family history:
- Essential tremor often has autosomal dominant inheritance 1
Physical Examination
- Observe tremor at rest, with sustained posture, and during movement
- Assess for distractibility (suggests psychogenic tremor)
- Evaluate for associated neurological findings:
- Bradykinesia, rigidity (Parkinson's disease)
- Cerebellar signs
- Dystonic posturing
- Lower limb weakness, abnormalities of gait or speech, tremor 4
- Blood pressure assessment 4
Diagnostic Testing
Laboratory Tests
- Basic metabolic panel, liver function, thyroid function, calcium, HbA1c 4
- Consider testing for Wilson's disease in young patients with tremor
Imaging and Other Tests
- Brain MRI if:
- Tremor with focal neurological abnormalities
- Asymmetric hearing loss
- Unilateral tremor
- Rapid progression
- For diagnostic uncertainty in suspected Parkinson's disease:
- Single-photon emission computed tomography (SPECT)
- Transcranial ultrasonography 1
Treatment Approach by Tremor Type
1. Essential Tremor
First-line pharmacotherapy:
Alternative medications:
For refractory cases:
2. Parkinsonian Tremor
- Levodopa/carbidopa: First-line treatment 7
- Dopamine agonists
- Anticholinergics (for younger patients with tremor-predominant disease)
- DBS for medication-refractory tremor
3. Physiologic and Enhanced Physiologic Tremor
- Identify and address underlying cause:
- Discontinue offending medications
- Reduce caffeine intake
- Treat hyperthyroidism, hypoglycemia 3
- Manage anxiety
4. Dystonic Tremor
- Anticholinergics
- Botulinum toxin injections (particularly effective for head and voice tremor) 6
5. Cerebellar Tremor
- Limited pharmacologic options
- Consider isoniazid, carbamazepine, or propranolol
- Weighted devices for severe cases
6. Psychogenic Tremor
- Cognitive behavioral therapy
- Short-term anxiolytics for acute episodes 3
- Multidisciplinary approach with psychiatry
Special Considerations
Elderly patients: Start with lower doses of propranolol (10-20mg twice daily) and titrate slowly 3
Comorbidities:
Head and voice tremor: Botulinum toxin injections may be more effective than oral medications 6
Monitoring:
- Assess treatment response using standardized tremor rating scales
- Monitor for side effects: bradycardia, hypotension, fatigue with beta-blockers; sedation, dizziness with primidone 3
Common Pitfalls to Avoid
- Misdiagnosis of tremor type leading to inappropriate treatment
- Inadequate dosing of beta-blockers
- Failure to address underlying causes (thyroid disease, medications)
- Overlooking drug interactions
- Delaying surgical referral for medication-refractory cases
Remember that tremor treatment should prioritize improvement in function and quality of life, with medication choices guided by tremor type, comorbidities, and patient-specific factors.