Tremor

Source: MedlinePlus Health Topics, U.S. National Library of Medicine

What is a tremor? A tremor is a neurological condition that includes shaking or trembling movements in one or more parts of your body. It most often affects the hands. But it can also affect the arms, legs, head, vocal cords, and torso (trunk). A tremor is involuntary, meaning that you cannot control it. It happens because of muscle contractions. A tremor may come and go, or it may be constant. It can happen on its own or be caused by another disorder. It is not life threatening, but it may cause challenges. It can make it hard to do daily life tasks such as writing, typing, eating, and dressing. In some cases, a tremor can even lead to disabilities . What are the types of tremor? There are several types of tremor, including: Essential tremor , sometimes called benign essential tremor or familial tremor. This is the most common type. It usually affects both your hands and arms while you are moving them. It can also affect your head, voice, or legs. Parkinsonian tremor , which is a common symptom in people who have Parkinson's disease . It usually affects one or both hands when they are at rest, but it can affect the chin, lips, face, and legs. Dystonic tremor , which happens in people who have dystonia . Dystonia is a movement disorder in which you have involuntary muscle contractions. The contractions cause you to have twisting and repetitive movements. It can affect any muscle in the body. What causes tremor? Generally, tremor is caused by a problem in the deep parts of the brain that control movements. For most types, the cause is unknown. Some types are inherited and run in families. There can also be other causes, such as: Neurologic disorders, including multiple sclerosis , Parkinson's disease, stroke , and traumatic brain injury Certain medicines, such as asthma medicines, chemotherapy , corticosteroids , and medicines used for certain psychiatric and neurological disorders Alcohol use disorder (AUD) or alcohol withdrawal Poisoning from certain toxic substanc