Essential Tremor (ET), also known as familial tremor, benign essential tremor, or hereditary tremor is a life-altering condition that turns simple everyday acts of living into tests of ingenuity and perseverance. Writing a letter, getting dressed, eating, applying makeup, shaving and handling tools take on a different perspective for people who have ET.

Tremor is the rhythmic shaking of a body part. Although it most commonly affects hands, arms, and head, it can also affect the jaw, face, and vocal cords, causing a quavering voice. ET rarely affects legs. ET is caused by miscommunication in certain parts of the brain, involving the cerebellum, thalamus, and brain stem.

Of the more than 20 kinds of tremor, ET is the most common. Experts estimate that over 10 million Americans have the condition – millions more than people diagnosed with Parkinson’s disease and more than twice as many as those with Alzheimer’s disease. In New Zealand, it has been estimated that 1-5% of the population is affected by ET.

ET is often misdiagnosed as Parkinson’s disease, but Parkinson’s and ET are entirely distinct conditions:

• Medication prescribed for Parkinson’s does not work in ET sufferers and vice-versa. See our page on Treatment to read more.
• ET tremors are different from Parkinson’s tremors, especially at rest and when attempting a focused action:
• • Parkinson tremors are continuous even at rest, ET tremors cease at rest.
  • ET tremors worsen with focused action such as bringing cup to mouth; Parkinson’s tremors relax with focused action. 
• Read more about the Types of Tremors experienced with ET.

There is no blood, urine, or other test for ET and it is not detected with MRI scan. Thus, whenever possible, seek advice from a neurologist with experience in movement disorders.

We should also bear in mind that ET is not a condition only of the elderly. Although average age of onset is the mid 40s, newborns and infants have been diagnosed with the condition. ET is largely genetic. That means each child of a parent with ET has a 50 percent chance of inheriting the condition. People who have no family history of ET, however, can develop the condition.