Hand Tremor Causes That Are Not Parkinson's Disease

Why do people assume tremor means Parkinson's?

Parkinson's disease is probably the best-known cause of tremor, and its associations with aging make it a common fear. But Parkinson's disease tremor — typically a resting tremor that is most visible when the hand is still and improves during intentional movement — is only one tremor type. Most people who come to a neurologist with hand tremor do not have Parkinson's disease 1Ref 1Zesiewicz TA, Elble RJ, Louis ED, et al. (2011).Evidence-based guideline update: Treatment of essential tremor: Report of the Quality Standards Subcommittee of the American Academy of Neurology.Essential tremor characteristics including action tremor vs resting tremor; distinction from Parkinson's disease; evidence-based pharmacological treatment. Understanding the distinctions helps direct appropriate evaluation.

What is essential tremor, and how common is it?

Essential tremor (ET) is the most common movement disorder in adults, increasing in prevalence with age. Its hallmark is an action tremor: it appears or worsens when the hands are in use — reaching, holding a cup, writing — and is typically absent or minimal when the hands are completely at rest 1Ref 1Zesiewicz TA, Elble RJ, Louis ED, et al. (2011).Evidence-based guideline update: Treatment of essential tremor: Report of the Quality Standards Subcommittee of the American Academy of Neurology.Essential tremor characteristics including action tremor vs resting tremor; distinction from Parkinson's disease; evidence-based pharmacological treatment.

ET most commonly affects the hands and arms, but can involve the head (a rhythmic "yes" or "no" movement), voice, or legs. It often runs in families. Unlike Parkinson's disease, ET does not cause the slowness of movement (bradykinesia), rigidity, or stooped posture that characterize parkinsonism 1Ref 1Zesiewicz TA, Elble RJ, Louis ED, et al. (2011).Evidence-based guideline update: Treatment of essential tremor: Report of the Quality Standards Subcommittee of the American Academy of Neurology.Essential tremor characteristics including action tremor vs resting tremor; distinction from Parkinson's disease; evidence-based pharmacological treatment.

Medications such as propranolol and primidone have Level A evidence for reducing ET tremor 1Ref 1Zesiewicz TA, Elble RJ, Louis ED, et al. (2011).Evidence-based guideline update: Treatment of essential tremor: Report of the Quality Standards Subcommittee of the American Academy of Neurology.Essential tremor characteristics including action tremor vs resting tremor; distinction from Parkinson's disease; evidence-based pharmacological treatment.

What other conditions cause hand tremor?

Physiologic tremor — everyone has a fine, barely visible tremor in their hands during sustained posture. Under certain conditions, this normal tremor becomes exaggerated: - High caffeine intake - Sleep deprivation - Physical exhaustion - Anxiety or acute stress - Low blood sugar (hypoglycemia)

Enhanced physiologic tremor from these causes is generally temporary and resolves when the trigger is removed.

Medication-induced tremor is an underappreciated cause. Many commonly used medications can cause or worsen tremor, including: - Certain psychiatric medications (lithium, valproate, some antidepressants, antipsychotics) - Asthma inhalers (albuterol) - Thyroid hormone replacement at too high a dose - Steroids and some immunosuppressants

Reviewing your medication list with a clinician is an important step if tremor began or worsened after starting a new medication 3Ref 3National Institute of Neurological Disorders and Stroke (2023).Peripheral Neuropathy.Overview of neurological causes of tremor and sensory symptoms; role of neurologist in evaluating unexplained neurological symptoms.

Hyperthyroidism (an overactive thyroid gland) causes a fine, rapid tremor, often accompanied by weight loss, fast heart rate, heat intolerance, and anxiety. A simple blood test (TSH) screens for this.

Anxiety disorders can produce tremor, particularly during periods of acute stress or panic. The tremor is generally action-type and often accompanied by other anxiety symptoms.

Alcohol use disorder — both active heavy alcohol use and alcohol withdrawal can produce tremor. Withdrawal-related tremor can be severe and is a medical emergency if it progresses to full delirium tremens.

Wilson's disease is a rare genetic condition of copper accumulation that can cause tremor in younger adults (under 40). It is always worth considering in younger patients with unexplained tremor.

Dystonic tremor occurs in the context of dystonia (sustained muscle contractions) and has characteristic features a neurologist can identify on examination.

How do clinicians distinguish essential tremor from Parkinson's?

The neurological examination is the starting point. A neurologist observes the tremor at rest, during posture (arms outstretched), and during intentional movement (reaching, drawing), assessing its pattern, frequency, and which body parts are affected 1Ref 1Zesiewicz TA, Elble RJ, Louis ED, et al. (2011).Evidence-based guideline update: Treatment of essential tremor: Report of the Quality Standards Subcommittee of the American Academy of Neurology.Essential tremor characteristics including action tremor vs resting tremor; distinction from Parkinson's disease; evidence-based pharmacological treatment.

Key distinguishing features:

| Feature | Essential Tremor | Parkinson's Tremor | |---|---|---| | When most visible | During movement | At rest | | Speed | Variable (4–12 Hz) | Typically 4–6 Hz, often described as "pill-rolling" | | Other motor signs | Usually absent | Slowness, rigidity, stooped posture, balance difficulty | | Head tremor | Common | Rare |

When clinical examination is uncertain, a DaTscan (a nuclear imaging study of dopamine transporters in the brain) can help distinguish ET from Parkinson's disease and related disorders 2Ref 2Elias WJ, Lipsman N, Ondo WG, et al. (2016).A Randomized Trial of Focused Ultrasound Thalamotomy for Essential Tremor.Clinical features and classification of essential tremor; DaTscan as a tool to distinguish essential tremor from Parkinson's disease in clinical trials.

When should I see a neurologist for hand tremor?

A neurology evaluation is appropriate when: - Tremor is new and unexplained - Tremor is interfering with daily activities - You are concerned about Parkinson's disease or another progressive condition - Tremor appeared alongside slowness, stiffness, or balance problems - Initial evaluation by a primary care clinician has not identified a clear cause

Many treatable causes — medication side effects, thyroid disease, anxiety — can be identified and addressed without specialist input. But when the cause is unclear, or when Parkinson's is a real possibility, a neurologist is the right resource 3Ref 3National Institute of Neurological Disorders and Stroke (2023).Peripheral Neuropathy.Overview of neurological causes of tremor and sensory symptoms; role of neurologist in evaluating unexplained neurological symptoms. Gale can help coordinate that referral.