Causes

Essential tremor is the most common type of tremor. Everyone has some tremor present, but the movements are often so small that they can't be seen. Essential tremors are most common in people older than 65.

The exact cause for essential tremor is unknown. Tremors occur when there is a problem with the nerves that supply certain muscles. Some research suggests that the part of the brain that controls muscles movements does not work correctly in patients with essential tremor.

Essential tremor can also occur with other brain and nervous system problems, such as dystonia, parkinsonism, and certain nerve conditions passed down through families.

If an essential tremor occurs in more than one member of a family, it is called a familial tremor. This type of essential tremor is passed down through families (inherited), which suggests that genes play a role in its cause.

Familial tremor is usually a dominant trait, which means that you only need to get the gene from one parent to develop the tremor. It often starts in early middle age, but may be seen in people who are older or younger.

Symptoms

The tremor is more likely to be noticed in the hands, but may affect the arms, head, eyelids, or other muscles. The tremor rarely affects the legs or feet. People with essential tremor may have trouble holding or using small objects such as silverware or a pen.

The shaking most often involves small, rapid movements -- more than 5 times a second.

Specific symptoms may include:

• Head nodding
• Shaking or quivering sound to the voice if the tremor affects the voice box
• Problems with writing, drawing, drinking from a cup, or using tools if the tremor affects the hands

The tremors may:

• Occur when you move (action-related tremor), and may be less noticeable with rest
• Come and go, but often get worse as you age
• Get worse with stress, caffeine, and certain medications
• Not affect both sides of the body the same way

Exams and Tests

Your doctor can make the diagnosis by performing a physical exam and asking questions about your medical and personal history.

A physical exam will show shaking with movement, usually small movements that are faster than 5 times per second. There are usually no problems with coordination or mental function.

Further tests may be needed to rule out other reasons for the tremors. Other causes of tremors may include:

• Smoking and smokeless tobacco
• Overactive thyroid (hyperthyroidism)
• Suddenly stopping alcohol after drinking a lot for a long time (alcohol withdrawal)
• Too much caffeine
• Use of certain medications

Blood tests and imaging studies (such as a CT scan of the head, brain MRI, and x-rays) are usually normal.

Treatment

Treatment may not be needed unless the tremors interfere with your daily activities or cause embarrassment.

HOME CARE

For tremors made worse by stress, try techniques that help you relax. For tremors of any cause, avoid caffeine and get enough sleep.

For tremors caused or made worse by a medication, talk to your doctor about stopping the drug, reducing the dosage, or switching. Do NOT change or stop medications on your own.

Severe tremors may make it harder to do daily activities. You may need help with these activities. Devices may help with everyday activities, such as:

Buying clothes with Velcro fasteners, using button hooks

Cooking or eating with utensils that have a larger handle

Using straws to drink

Wearing slip-on shoes and using shoehorns

MEDICINES FOR TREMOR

Medicines may help relieve symptoms. The most commonly used drugs include:

• Propranolol, a beta blocker
• Primidone, a drug used to treat seizures

The drugs can have side effects.

• Propranolol may cause fatigue, stuffy nose, or slow heart beat, and may make asthma worse
• Primidone may cause drowsiness, problems concentrating, nausea, and problems with walking, balance, and coordination.

Other medications that may reduce tremors include:

• Antiseizure drugs such as gabapentin and topiramate
• Mild tranquilizers such as alprazolam or clonazepam
• Blood pressure drugs called calcium-channel blockers such as flunarizine and nimodipine

Botox injections, given in the hand, have been used to reduce tremors by weakening local muscles.

SURGERY

In severe cases, surgery may be tried. This may include:

• Focusing high-powered x-rays on a small area of the brain (stereotactic radiosurgery)
• Implanting a stimulating device in the brain to signals the area that controls movement

Outlook (Prognosis)

An essential tremor is not a dangerous problem, but some patients find the tremors annoying and embarrassing. In some cases, it may be dramatic enough to interfere with work, writing, eating, or drinking.

Possible Complications

Sometimes the tremors affect the voice box, which occasionally leads to speech problems.

When to Contact a Medical Professional

Call for your health care provider if

• You a have a new tremor
• Your tremor makes it hard to perform daily activities
• You have side effects from in the drugs used to treat your tremor

Prevention

Alcoholic beverages in small quantities may decrease tremors but can lead to alcohol dependence and alcohol abuse, especially if you have a family history of such problems. How alcohol helps relieve tremors is unknown.

Alternative Names

Tremor - essential; Familial tremor; Tremor - familial

References

Deuschl G, Raethjen J, Hellriegel H, Elble R. Treatment of patients with essential tremor. Lancet Neurol. 2011 Feb;10(2):148-61.

Update Date: 3/31/2012

Reviewed by: Kevin Sheth, MD, Department of Neurology, University of Maryland School of Medicine, Baltimore, MD. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine;David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.