image donateEssential tremor is a type of uncontrollable shake or tremble of part of the body. 

Most people with essential tremor experience a trembling, up-and-down movement of the hands. 

The arms, head, eyelids, lips and other muscles can also be affected. A tremor in the voice box (larynx) may cause a shaky voice.

Essential tremor is usually more noticeable when you're trying to hold a position or do something with your hands, such as write. It doesn't always affect both sides of the body equally.

Essential tremor is a common movement disorder affecting around four out of 100 adults over 40 years of age. Some people only have a mild tremor at first, which usually gets more severe over time.