Harvard Women's Health Watch

This condition is less well known than Parkinson's disease, but it's far more common.

For many, the late actress Katharine Hepburn provided an indelible public image of essential tremor. Her quavering voice and trembling hands unmistakably betrayed the disorder. About 10 million people in the United States manifest symptoms of the condition, which variably causes the hands, head, and voice to shake.

For women with essential tremor, holding a coffee cup, writing a note, buttoning a sweater and applying makeup can all be challenging and sources of frustration or embarrassment. When the condition interferes with independent living or holding a job, it can be devastating. Fortunately, there are medications that help control the symptoms, and ways to make the tasks of daily living easier.


The symptoms often first appear in a person's 40s, when delicate movements such as threading a needle become difficult. But it's usually not until people reach their 50s or 60s that the tremor becomes troublesome -- for example, making it difficult to use a fork, drink from a cup or write a letter. Essential tremor progresses slowly. Though it may eventually affect the voice and head, many people find that their symptoms don't progress beyond mild hand and arm tremor. Tremors are usually absent during sleep.

We don't know the precise cause of essential tremor. Some experts believe that the problem lies in the cerebellum (the part of the brain that controls movement and balance) or its connections with the brainstem, which lies at the base of the brain. Essential tremor is a heritable condition. If you have the disorder, your children will have a 50 percent chance of developing it as well.


Essential tremor is often mistaken for Parkinson's disease, but the two conditions differ in several ways. Essential tremor is an action tremor, meaning that the involuntary shaking increases when you move and try to use your hands. In Parkinson's disease, tremors occur mainly at rest, and activity reduces the symptoms. Some people with essential tremor develop head nodding or shaking; few people with Parkinson's do. Balance problems and rigidity of the arms and legs are common features of Parkinson's disease but not of essential tremor. One of the hallmarks of essential tremor, useful in diagnosing the disorder, is that alcohol can temporarily ease symptoms; in Parkinson's, alcohol has little effect on the tremor.

Parkinson's disease is marked by a progressive loss of brain cells that produce dopamine, a chemical messenger that enables normal body movements. Essential tremor also appears to involve a disruption in the activity of motor pathways, but it's uncertain whether there is any loss of brain cells. Postmortem examinations of brain tissue taken from people with essential tremor reveal various abnormalities in the cerebellum and brainstem, including the loss of Purkinje cells, which produce an important neurotransmitter, called GABA. But the samples don't all show the same changes, so the import of these findings is uncertain.


Here are some ways to minimize the effects of tremors on your daily life:

-- Avoid caffeine; it can aggravate symptoms.

-- Use mugs with lids and straws for beverages and soups.

-- Use a small recorder to take and play back notes, including your grocery list.

-- To control head tremor, turn your head to the side.

-- To reduce tremors when you're using your hands, hold your elbows close to your body.

-- When you apply makeup, rest your elbows on a table or countertop.

-- Use salon services for manicures and eyebrow care.

-- Adopt a hairstyle that requires a minimum of fuss.

-- Use debit or credit cards instead of writing checks.

-- At a restaurant, ask the wait staff to serve foods such as meat in bite-sized pieces.

Sources: Adapted, in part, from "Coping with Essential Tremor," from the International Essential Tremor Foundation (IETF). For a more extensive list of coping tips from IETF, go to www.essentialtremor.org.


There's no cure for essential tremor, but the symptoms can be managed in several ways, starting with practical measures such as those listed above in "Tips for surviving essential tremor." Therapies include medications and surgery. In 2005, the American Academy of Neurology formulated practice guidelines in which these approaches were ranked by the quality of the scientific evidence supporting them. The conclusions:


Propranolol (Inderal) and primidone (Mysoline) are most effective in reducing tremors. Propranolol is a beta blocker, also used to treat high blood pressure and performance anxiety. Its side effects are mild to moderate and include slow heartbeat, fatigue, and shortness of breath. (People with asthma should not take propranolol.) Primidone is an antiseizure medication with mild to moderate side effects that include drowsiness, difficulty concentrating, nausea, and dizziness. Both of these drugs can reduce tremors by as much as 50%.

Several other drugs may be helpful, though the evidence for them isn't as strong. These include the anti-anxiety drug alprazolam (Xanax); the beta blockers atenolol (Tenormin) and sotalol (Betapace); and the antiseizure drugs gabapentin (Neurontin) and topiramate (Topamax).


If medications don't help, surgery may. Surgery always carries risk, and the risk is especially great for operations involving the brain. The two best-studied surgical treatments for severe limb tremor that hasn't responded to medications are thalamotomy and deep brain stimulation (DBS). Both procedures can help reduce limb tremors; they may be less useful for head shaking and a quavering voice.

During thalamotomy, a probe is inserted through a small hole in the skull into the brain, where it destroys part of the thalamus, a deep brain structure involved in involuntary muscle movement. Studies have found that thalamotomy reduces or suppresses limb tremor in 80 to 100 percent of patients treated for essential tremor, but adverse events occur in 14 to 47 percent of patients. Serious long-lasting complications occur in about 4 percent and include sometimes permanent weakness on one side of the body and difficulty with speech and swallowing.

DBS involves placing electrodes in the brain and connecting them to a pacemaker-like device implanted in chest. Small electric impulses sent from the device to the brain interrupt communications between the cells that cause tremors. DBS is now generally preferred to thalamotomy because it's largely reversible and the device can be adjusted to reduce side effects. Reduced limb tremor is found in 70 to 90 percent of patients. Adverse effects, which include weakness, imbalance, and numbness, occur in about 18 percent of patients and are generally short-lived. Serious long-term complications occur in about 1 to 3 percent of patients.


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Health - Essential Tremor and How to Manage It