Diseases & Conditions

Benign Essential Tremor - Essential Tremor

Overview, Causes, & Risk Factors

Essential tremor, also called ET, is uncontrollable shaking of the hands or head. It can also affect other parts of the body, but hands are most common. ET usually affects both hands. Other areas that may be involved include:

  • voice
  • tongue
  • legs
  • trunk
  • The shaking is most often a back-and-forth movement.

    What is going on in the body?

    No one knows exactly what happens in the body to cause these visible tremors. They are not life threatening, but they can make it hard for a person to function in daily life.

    What are the causes and risks of the condition?

    Heredity is the only known cause or risk for ET. Fifty to sixty percent of people with ET have a family history. When there is a family history of a similar tremor, the condition is called familial tremor. The trembling can get worse with the following:

  • stress, or emotion
  • hunger
  • fatigue
  • caffeine
  • temperature extremes
  • ET affects men and women equally. It is more likely to strike people as they age.

    Symptoms & Signs

    What are the signs and symptoms of the condition?

    The symptoms of ET include patterned trembling in one or both hands and sometimes the head. The voice may also be shaky. The tremors are mostly mild and only happen once in awhile at first. But they slowly worsen with age.

    The tremors are more obvious when the hands are in use. Rest relieves them in most cases.

    Diagnosis & Tests

    How is the condition diagnosed?

    The doctor will diagnose ET by seeing a person have tremors. The doctor will sometimes use an electromyography test, called EMG, to confirm the diagnosis. This kind of test checks the electrical activity in a set of muscles. An overactive thyroid gland, called hyperthyroidism, can mimic essential tremor. Blood tests can help rule out this condition.

    A person who comes to a doctor with ET is often concerned about Parkinson disease. A doctor can usually tell these two types of tremors apart.

    Prevention & Expectations

    What can be done to prevent the condition?

    At this time, there is no known way to prevent ET.

    What are the long-term effects of the condition?

    Over time, the tremor can become severe enough to make it hard to do anything that calls for fine motor skills, such as:

  • writing
  • eating
  • drinking
  • dressing
  • The loss of function and embarrassment often affect quality of life. Over time, ET gets worse. This means that either the tremors become more pronounced, or they come more often.

    Treatment & Monitoring

    What are the treatments for the condition?

    First-choice medicines used to treat this condition include:

  • propranolol, a beta-blocker
  • primidone, an anticonvulsant
  • Propanolol is used more often in younger people, while primidone is often the first choice for the older person. At times, these medicines may even be used together. When neither of those medicines helps, clonazepam may be used. Early treatment is key, because it will often prevent disability.

    Other medicines sometimes used to treat ET include:

  • benzodiazepines, such as lorazepam, alprazolam, or diazepam
  • nadolol, a heart medicine
  • methazolamide
  • gabapentin
  • Doctors can also do a surgery that stimulates the thalamus, which is the part of the brain that relays sensory information. But this treatment is only used in severe cases, which do not respond to medicine.

    Physical therapy can help a person adapt to the tremors. One- to two-pound weights strapped to the wrists may help make hands more steady.

    What are the side effects of the treatments?

    Potential side effects of the medicines used include:

  • fatigue
  • light-headedness
  • sleepiness
  • Potential risks of surgery include infection and bleeding in the brain.

    What happens after treatment for the condition?

    The tremors will often improve with medicine or surgery. But they can rarely be completely stopped. A person may find that symptoms grow worse with time, but this varies.

    How is the condition monitored?

    Any new or worsening symptoms should be reported to the doctor.


    Author:Michael Curiel, MD
    Date Written:
    Editor:Crist, Gayle P., MS, BA
    Edit Date:04/10/02
    Reviewer:Kathleen A. MacNaughton, RN, BSN
    Date Reviewed:04/08/02