Essential tremor is the most common type of tremor. Everyone has some tremor present, but the movements are often so small that they cannot be seen. Essential tremor affects men and women and is most common in people older than 65.
The exact cause of essential tremor is unknown. Some research suggests that the part of the brain that controls muscle movements does not work correctly in patients with essential tremor.
If an essential tremor occurs in more than one member of a family, it is called a familial tremor. This type of essential tremor is passed down through families (inherited). This suggests that genes play a role in its cause.
Familial tremor is usually a dominant trait. This means that you only need to get the gene from one parent to develop the tremor. It often starts in early middle age, but may be seen in people who are older or younger.
The tremor is more likely to be noticed in the hands. The arms, head, eyelids, or other muscles may also be affected. The tremor rarely occurs in the legs or feet. A person with essential tremor may have trouble holding or using small objects such as silverware or a pen.
The shaking most often involves small, rapid movements occurring more than 5 times a second.
Specific symptoms may include:
Shaking or quivering sound to the voice if the tremor affects the voice box
Problems with writing, drawing, drinking from a cup, or using tools if the tremor affects the hands
The tremors may:
Occur during movement (action-related tremor) and may be less noticeable with rest
Come and go, but often get worse with age
Worsen with stress, caffeine, and certain medications
Not affect both sides of the body the same way
Exams and Tests
Your doctor can make the diagnosis by performing a physical exam and asking questions about your medical and personal history.
A physical exam will show shaking with movement, usually small movements that are faster than 5 times per second. There are usually no problems with coordination or mental function.
Further tests may be needed to rule out other reasons for the tremors. Other causes of tremors may include:
Implanting a stimulating device in the brain to signal the area that controls movement
An essential tremor is not a dangerous problem. But some patients find the tremors annoying and embarrassing. In some cases, it may be dramatic enough to interfere with work, writing, eating, or drinking.
Sometimes the tremors affect the vocal cords, which may lead to speech problems.
When to Contact a Medical Professional
Call your health care provider if:
You have a new tremor
Your tremor makes it hard to perform daily activities
You have side effects from the medicines used to treat your tremor
Alcoholic beverages in small quantities may decrease tremors. But alcohol abuse may develop, especially if you have a family history of such problems.
Jankovic J. Movement disorers. In: Daroff RB, Fenichel GM, Jankovic J, Mazziotta JC, eds. Bradley's Neurology in Clinical Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 71.
Joseph V. Campellone, M.D., Division of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.