Tremors
Tremors are involuntary shaking that is repeated over and over. Tremors can affect any part of your body, but most often affects the hands or head. Essential tremors ,which can sometimes run in the families, is the most common type of tremor. Tremors can be caused by medications or conditions that affect the nervous system, including Parkinson’s disease, liver failure, alcoholism, mercury or arsenic poisoning, lithium, and certain antidepressants.
source: www.webmd.com/parkinsons-disease/tc/tremor-topic-overview
