What causes hand tremors?
Could a tremor in one hand be Parkinson’s disease?Distinguishing between tremors at rest and tremors during activity.
Observing when the tremor occurs, which side it affects, and what other symptoms are present will help you have a more focused discussion with your doctor.
Becomes more pronounced with stress, fatigue, or coffee consumption.
Subgroup 14, Age ≥65 years (2021)
Often begins asymmetrically (affecting one side more than the other).
Could be a stroke.
Many people notice their parents’ hands shaking while holding a glass of water, or observe their fingers trembling while they sit watching TV, and worry about what it might be.Parkinson’s diseaseIn reality, there are many different types of tremors.
General information only—not a medical diagnosis. No medication is recommended here;do not stop or adjust any prescribed medication on your own.
In this article:
1. What Causes Hand Tremors?Common Reasons
In short:Hand tremors can range from normal, subtle shaking—which may become more noticeable due to stress, fatigue, or caffeine consumption—to tremors caused by medications, thyroid dysfunction, or neurological conditions such as essential tremor and Parkinson’s disease.Doctors distinguish between these causes by observing the characteristics of the tremor and any accompanying symptoms.
According to the NHS:It is normal for most people to experience mild tremors.These may become more apparent with age, stress, fatigue, anxiety, or the consumption of caffeine, alcohol, or tobacco. Exposure to extreme heat or cold can also trigger them.Certain medications and medical conditions can cause tremors, and in some cases, they may run in families.
Observe whether the tremors occur during activity—such as when holding a cup—or while the hands are at rest.
2. What Is the Difference Between Resting Tremors and Action Tremors?
In short:Resting tremor refers to involuntary shaking that occurs when the hands are resting—for example, while sitting with hands on one's lap—without any intentional movement.This type of tremor typically decreases when the hands are put to use;it is a hallmark of Parkinson’s disease. Action tremor (or kinetic tremor) occurs during activity, such as holding the hand in a fixed position, holding a glass, writing, or eating. This type is often associated with essential tremor, or it may be triggered by medications, thyroid issues, or caffeine consumption.
| Observation | Resting tremor | Action tremor |
|---|---|---|
| When does it occur? | Hands resting on the lap | Holding the hand in a fixed position, holding a glass, scooping food, writing |
| Upon initiating movement | Usually decreases or stops temporarily | Becomes more pronounced |
| Which side? | Often begins on one side | Often affects both sides (essential tremor) |
| Associated symptoms to mention to your doctor | Slowness of movement, muscle stiffness | Tremor in the head or voice;family history of similar tremors |
| Consider | Parkinson’s disease | Essential tremor · Medications · Thyroid · Caffeine |
Summarized from MDS (2018) and the NHS;this information serves as a guide for your doctor’s visit, not for self-diagnosis.Parkinson’s disease can involve tremors during movement (action tremors), while some cases of Essential Tremor (ET) may present with tremors at rest—a condition classified as "ET plus."Therefore, a thorough evaluation of accompanying symptoms is necessary.
3. Could a tremor in only one hand indicate Parkinson’s disease?
In short:A tremor in one hand that occurs at rest and gradually worsens can be a sign of Parkinson’s disease.However, a physician must confirm the presence of slowness of movement (bradykinesia) and rule out other conditions before making a diagnosis. If you experience sudden weakness, numbness, or slurred speech, call 1669 immediately.
According to the MDS criteria (Postuma et al., 2015), it is considered that...Slowness of movement accompanied by resting tremors or muscle rigidityThese are signs of parkinsonism.Before confirming a diagnosis of Parkinson’s disease, a physician must apply exclusion criteria and look for "red flags" that might indicate other conditions;therefore, a tremor alone is not sufficient for a diagnosis. According to the Movement Disorder Society (MDS) guidelines (2018), tremors associated with Parkinson’s disease are typically asymmetrical—often beginning on one side of the body.While tremors occurring at rest or during activity can serve as clues, they are not definitive diagnostic markers.
- Additional observationsSignificant slowing of daily activities, muscle rigidity, and difficulty with physical movement or facial expressions (NHS).
- Read more about Parkinson’s disease. Treating Parkinson’s disease with physical therapy.andRehabilitation for Parkinson’s: Slowing the progression of the disease through physical therapy.
The physician assesses tremors—both at rest and during activity—in conjunction with other movement patterns.
4. What is essential tremor, and how does it differ from Parkinson’s disease?
In short:Essential tremor is a syndrome characterized by tremors occurring during the use of both upper limbs, persisting for at least 3 years, in the absence of other neurological signs such as muscle spasms, gait instability, or symptoms of Parkinson’s disease.If the clinical features are consistent with essential tremor but the duration is less than 3 years, the condition is classified as "indeterminate tremor" and is not yet considered essential tremor under these criteria.
A review by Louis and McCreary (2021) encompassed 42 population-based studies. Among a subset of 14 studies that utilized clear definitions and included data for individuals aged ≥65 years, the pooled prevalence was found to be:5.79%(95% CI 4.14–8.05%). Prevalence increases with age and does not differ significantly between genders; however, there is high heterogeneity among the studies (I² 96.3%), necessitating cautious interpretation.Furthermore, these figures are not specific to the Thai population.
- Typically bilateral (affecting both sides).May be accompanied by tremors of the head or voice.
- Not consistent with essential tremor.If the onset is sudden or the condition worsens in a stepwise manner, physicians will investigate other potential causes.
- TreatmentFor tremors that interfere with daily life, physicians may consider treatments to alleviate symptoms.According to the NHS, certain medications can help reduce tremors, though they do not provide a permanent cure.
5. Hand tremors caused by medication, thyroid issues, caffeine, and stress
In short:If a doctor determines that the tremors are an "enhanced physiological tremor" resulting from a treatable cause—such as an overactive thyroid or the use of certain medications—the symptoms may resolve once the underlying cause is addressed.Do not stop taking any medication on your own;always consult a doctor or pharmacist first.
- MedicationsCertain medications can cause tremors.If you notice tremors starting after beginning a new medication or adjusting the dosage of an existing one, bring all your medications to show your doctor or pharmacist.Do not stop taking medication on your own.
- Overactive Thyroid (Thyrotoxicosis)If hand tremors are accompanied by heart palpitations, weight loss despite a good appetite, heat intolerance, or excessive sweating (NHS), you should see a doctor for a blood test.
- Caffeine, Alcohol, and TobaccoThese can make tremors more pronounced (NHS).Some individuals with Essential Tremor (ET) report a reduction in tremors after consuming a small amount of alcohol;however, this effect is inconsistent and is not used as a diagnostic criterion.Do not consume alcohol as a form of self-medication.
- Stress and FatigueThese can make tremors more noticeable.
6. When should you see a doctor for hand tremors?When should you call 1669?
In short:See a doctor if your hand tremors worsen, interfering with activities like eating, writing, or getting dressed.Seek medical attention if you experience tremors on one side while at rest, slowness of movement, changes in your gait, or sudden weakness, numbness, facial drooping, slurred speech, or loss of balance—regardless of whether or not you have tremors—by calling 1669 immediately.
Call 1669 immediately
• Sudden weakness or numbness on one side of the body, facial drooping, or slurred speech (signs of a stroke; tremors may or may not be present).
• Tremors accompanied by chest pain or tightness, severe heart palpitations, or difficulty breathing.
Even if symptoms resolve on their own, you should still go to the hospital.BEFAST: Warning signs of a stroke
- Schedule a doctor's appointmentTremors on one side while at rest, slowness in performing tasks, muscle stiffness, or the onset of falls.
- Schedule a doctor's appointmentTremors that are progressively worsening or interfering with daily life (NHS).
- Schedule a doctor's appointmentTremors accompanied by weight loss, heart palpitations, or tremors that began after a change in medication.
For gait and balance training, following a medical diagnosis
“A trembling hand doesn’t always mean it’s Parkinson’s disease. Observe the symptoms carefully and consult a doctor to get an accurate answer sooner.”
How can KIN Hospital (Sukhumvit 107) assist your family?
Located in Soi Bearing 10, near BTS Bearing, KIN Hospital (Sukhumvit 107) is a registered rehabilitation hospital.Not an emergency room.Following a medical diagnosis, our team provides support with walking and balance.
- Our medical team includes a neurologist.We provide ongoing care through scheduled appointments, with a multidisciplinary team covering 5 medical specialties and 8 allied health professions.Viewour team list.
- We offer balance assessment and gait training to prevent falls—including for patients with Parkinson’s disease.Conducted by physical therapists using standardized balance assessment tools.ViewPhysical therapy for Parkinson’s disease patients.
- Outpatient Physical TherapyPersonalized training plans based on assessment results
- Inquiries and facility tours available daily (free of charge)09:00–18:00 (Excludes medical examinations/treatments)
Contact KIN Hospital, Sukhumvit 107 |Free consultations and facility tours
Balance assessment and gait training for those with tremors · For sudden-onset symptoms accompanied by weakness, please call 1669 first
Other KIN Rehabilitation locations
Central Hotline:02-096-4996| In-home Physical Therapy: 095-767-6307 | Nursing Care & Equipment Rental: 061-881-9399 |For emergencies, call 1669
Frequently Asked Questions – Answered by KIN’s medical and multidisciplinary team
What causes hand tremors?
There are many possible causes—ranging from normal tremors that become more noticeable due to stress, fatigue, or caffeine consumption, to side effects from certain medications, hyperthyroidism, essential tremor, or Parkinson’s disease.Physicians distinguish between these conditions based on the characteristics of the tremor and any accompanying symptoms.
Does a tremor in only one hand indicate Parkinson’s disease?
It is possible if the tremors occur while at rest and gradually worsen; however, a doctor must first observe for associated slowness of movement and rule out other conditions before making a diagnosis.If a tremor appears suddenly on one side of the body, accompanied by weakness or slurred speech, call 1669 immediately.
What causes hand tremors when holding a glass or writing?
These are "action tremors" (tremors that occur during movement). They can be associated with essential tremor, or exacerbated by medications, thyroid issues, caffeine, or stress.You should see a doctor if the tremors worsen or interfere with your daily life.
Which medical department should I visit for hand tremors, and what kind of examinations are involved?
You can start by seeing a general practitioner or an internist.The doctor will ask about your symptoms, medications you are taking, and your family medical history, followed by a physical examination.If a specific condition is suspected, you may be referred to a specialist, such as a neurologist. If a thyroid issue is suspected, blood tests will be performed.Note that there is no blood test that can diagnose Parkinson’s disease.
Can thyroid problems cause hand tremors?
Yes. An overactive thyroid (thyrotoxicosis) can cause hand tremors, often accompanied by heart palpitations, weight loss, heat intolerance, and excessive sweating. You should see a doctor for blood tests.
I’ve developed hand tremors after taking medication—can I stop taking it on my own?
You should not stop taking medication on your own, as doing so could negatively affect the condition the medication is intended to treat.Instead, bring all your medications to a doctor or pharmacist to determine whether the tremors are related to the medication.
- Consensus Statement on the classification of tremors — Bhatia KP et al., Mov Disord, 2018
- MDS clinical diagnostic criteria for Parkinson's disease — Postuma RB et al., Mov Disord, 2015
- How Common is Essential Tremor?Update on the Worldwide Prevalence — Louis ED, McCreary M, Tremor Other Hyperkinet Mov, 2021
- Tremor or shaking hands — NHS (reviewed 2023)
- Parkinson's disease: Symptoms — NHS (reviewed 2022)
- Overactive thyroid: Symptoms · Diagnosis — NHS
- MDS Position Statement on the Diagnosis of Parkinson's Disease (2023)
- Stroke: Symptoms — NHS (reviewed 2024)
Medically reviewed by Dr. Krittha Phuengcharoen (License No. 40781), Neurologist |Supervised by Dr. Thongchai ChokthanomsapChief Executive Officer | Last updated: Oct 2026 |This article provides general information only;it is not a medical diagnosis or personalized medical advice.It does not recommend any specific medication. Do not stop or adjust your medication on your own.Research statistics do not necessarily reflect the outcomes for patients receiving services at KIN.