What Is a Tremor?
A tremor is an involuntary, rhythmic shaking movement that can affect the hands, arms, head, voice, legs, or trunk. Tremors are one of the most common movement disorders and can range from barely noticeable to severe enough to interfere with daily activities like writing, eating, or dressing. Not all tremors indicate a serious problem — some are temporary and harmless, while others point to an underlying neurological condition.
Types of Tremor
- Resting tremor: Occurs when the affected body part is relaxed and supported, and often decreases with movement. Commonly associated with Parkinson’s disease.
- Action tremor: Occurs with voluntary movement. Includes several subtypes:
- Postural tremor: Present when holding a position against gravity, such as arms outstretched
- Kinetic tremor: Occurs during movement, such as reaching for an object
- Intention tremor: Worsens as movement approaches its target,often linked to cerebellar problems
- Essential tremor: The most common cause of action tremor, typically affecting the hands, and often runs in families
- Physiologic tremor: A very fine, usually unnoticeable tremor present in everyone, which can become more visible with stress, caffeine, or fatigue
Common Causes
- Essential tremor: A neurological condition, often hereditary, distinct from Parkinson’s disease
- Parkinson’s disease: Classic resting tremor, often starting on one side
- Enhanced physiologic tremor: Triggered by stress, anxiety, caffeine, fatigue, or certain medications
- Medication side effects: Including some antidepressants, asthma medications, and mood stabilizers
- Alcohol withdrawal
- Overactive thyroid (hyperthyroidism)
- Cerebellar disorders: Affecting coordination and balance
- Neurological conditions: Such as multiple sclerosis or stroke affecting movement-control pathways
How Is Tremor Evaluated?
- Detailed medical history, including when the tremor occurs and what makes it better or worse
- Neurological examination
- Blood tests to check thyroid function or rule out metabolic causes
- Review of current medications
- Imaging, such as MRI, if a structural cause is suspected
- Specialized tests to help distinguish essential tremor from Parkinsonian tremor
Managing Tremors
Treatment depends on the underlying cause and severity:
- Addressing reversible causes: Such as adjusting medications or treatingthyroid problems
- Lifestyle adjustments: Reducing caffeine and alcohol, managing stress, and getting adequate rest
- Medications: Beta-blockers or certain anticonvulsants are commonly used for essential tremor
- Physical or occupational therapy: To help with daily function and reduce tremor impact
- Assistive devices: Weighted utensils or adaptive tools for daily tasks
- Advanced options: Such as focused ultrasound or deep brain stimulation, for select cases with severe, treatment-resistant tremor
When to See a Doctor
Consult a doctor if a tremor is new, worsening, interfering with daily activities, or accompanied by other symptoms such as slowness of movement, stiffness, balance problems, or weakness. A proper evaluation can help identify the underlying cause and guide the most effective treatment.