Essential tremor—also called benign essential tremor—is a neurological (brain) disorder that causes a part of your body to shake uncontrollably. The shaking is called tremors. The hands and forearms are the most commonly affected areas, but the head, face, tongue, neck, mid-body, voice box, and rarely, the legs and feet can be affected. Other conditions, such as Parkinson’s disease, can cause tremors, but with essential tremor, there is no known underlying condition. Essential tremor is not life threatening and does not cause any health problems.
According to the International Essential Tremor Foundation, essential tremor is a common disorder, affecting approximately 10 million people in the Unites States (IETF, 2012). The tremors can begin at any age, but elderly people are most commonly affected. The exact cause of essential tremor is unknown.
Tremors, in general, can be caused by a variety of conditions like Parkinson’s disease, overactive thyroid, alcoholism and stroke. These tremors are not characterized as essential tremor.
The exact cause of essential tremor is unknown. Scientists have not found absolute genetic or environmental causes, and no cellular defect has been linked to the condition. According to researchers at Columbia University, however, there is some evidence that cells in the cerebellar cortex region of the brain shrink or disappear in people with essential tremor (Columbia). As with most medical conditions, research is ongoing.
The tremors experienced with essential tremor are small, rapid movements. You may experience tremors all the time, occasionally, or intermittently. Both sides of your body may or may not be equally affected. In the majority of cases, the tremors occur when a person is trying to do something (action tremors). According to Harvard Medical School, up to 20 percent of people will experience tremors when they are not doing anything (Harvard). This is called “tremors at rest.”
Tremors can range from minor to severe. Your tremors may be so minor that they do not affect your life, or they may be severe enough to interfere with normal activities. The symptoms of essential tremor in different parts of the body include:
Hand and Arms
You may experience shakiness in the hands or arms that is usually most noticeable when trying to perform activities using the hands.
Head and Neck
Your head may shake in an up-and-down or side-to-side motion.
Parts of your face may appear to twitch, such as your eyelids.
Tongue and Voice Box
Tremors in the tongue or voice box can make your voice sound shaky when you are speaking.
Mid-body, Legs, and Feet
Tremors in your core, legs, and feet can cause balance difficulties or make your gait (the way you walk) appear abnormal.
Certain factors may make your tremors temporarily worse, including:
- emotional stress
- very cold or very hot temperatures
- caffeinated drinks
- smoking cigarettes
Essential tremor can be inherited, but it can also occur without a family history. According to the National Institute of Neurological Disorders and Stroke, if you have essential tremor, your child has a 50 percent chance of developing the disorder (NINDS).
When there is a family history of essential tremor, it is called familial tremor.
Doctors diagnose essential tremor by observing the tremors and by ruling out other causes. Your doctor may perform a physical exam to evaluate the degree of your shakiness, and tests such as CT scans, MRI scans, and X-rays to determine if you have any abnormalities. If you only have essential tremor, the CT and MRI scans and X-rays should be normal. Other, underlying causes (like Parkinson’s, for instance) can be identified through testing and treated accordingly.
There is no cure for essential tremors. There are treatments that may reduce your symptoms. You may not require treatment if your symptoms are minor. If your symptoms severely affect your life, your doctor may advise treatment. Treatment options include:
- beta-blocker medications such as propranolol (these medications limit adrenaline, which can worsen tremors)
- anticonvulsant medications such as primidone, which work to reduce excitability of nerve cells
- mild tranquilizers such as alprazolam
- blood pressure medications such as flunarizine, which limit adrenaline
- botox injections in the hands to weaken the muscles and minimize or stop shaking
- physical therapy to improve coordination and muscle control
Surgery is considered only as a last resort when other treatments fail to provide relief. Surgical options include:
- deep brain stimulation (small electrodes are implanted in the area of your brain that controls movement to block the nerve signals that cause tremors)
- stereotactic radiosurgery (high-powered X-rays are pinpointed on a small area of the brain to correct tremors)
For unknown reasons, a small amount of alcohol (one alcoholic beverage or less) reduces tremors in some people. However, drinking alcohol is not recommended as a treatment because it can lead to dependence.
Many people with essential tremor live normal lives. The famous actress Katharine Hepburn led a successful career and had essential tremor that affected her head and voice.
If your tremors are severe enough, you may have to make some adjustments, such as wearing slip-on shoes, using a buttonhook to fasten buttons, using straws to drink, or using an electric razor instead of a manual razor.
Your tremors may stay relatively the same or they may progressively worsen. The tremors may also spread to other areas of your body.
There is conflicting research regarding the risks associated with essential tremor. Some research suggests that people with essential tremor have a higher risk of developing Parkinson’s disease or sensory problems such as loss of smell or hearing; however, other research suggests that people with essential tremor have an increased lifespan (NLM, 2012).