Tremors are unintentional trembling or shaking movements in one or more parts of your body. Most tremors occur in the hands. You can also have arm, head, face, vocal cord, trunk and leg tremors. Tremors are most common in middle-aged and older people, but anyone can have them.
Tremors commonly occur in otherwise healthy people. Sometimes, however, nerve diseases such as Parkinson’s disease or dystonia, an overactive thyroid, or certain medicines can cause them. Heavy drinking, because it kills certain nerve cells, can cause tremors, too. Some forms are inherited and run in families. Others have no known cause.
There is no cure for most tremors. Treatment to relieve them depends on their cause. In many cases, medicines and sometimes surgical procedures can reduce or stop tremors and improve muscle control. Tremors are not life threatening. However, they can be embarrassing and make it hard to perform daily tasks.
NIH: National Institute of Neurological Disorders and Stroke