The term trembling is generally used to describe involuntary or unintentional shaking.
Many people have experienced trembling before. It can happen when a person is cold or nervous. However, trembling has many causes, and some of those causes can be quite serious.
There are many possible causes of trembling. These include:
Other causes are also possible. Sometimes, no cause can be found.
When a person complains of trembling, the healthcare provider will want to know:
Other questions may also be asked.
Diagnosis begins with the history and physical exam. This may be all that is needed to figure out the cause. Further tests are needed in other cases.
The tests ordered will depend on the suspected cause. For example, thyroid function blood tests can detect hyperthyroidism. A blood glucose level can detect hypoglycemia.
An electroencephalogram, or EEG, is a test that can be used to detect seizures. It involves taping several wires to the scalp to measure the electricity in the brain, often called brain waves. Special x-rays of the brain, such as a cranial CT scan, may be ordered if brain damage is suspected.
Prevention is related to the cause. Most cases cannot be prevented. Avoiding alcohol can prevent cases due to alcohol withdrawal. Avoiding the cold can prevent some cases due to feeling chilled.
Long-term effects are related to the cause. For example, cases due to cold or fatigue often have no long-term effects. Cases due to nervous system damage may result in death or permanent disability.
Trembling is not contagious and poses no risk to others.
Treatment is directed at the cause, if one can be found. For example, myoclonus can often be treated with medications called benzodiazepines, such as diazepam. Someone who trembles because of seizures can be treated with medications to stop the seizures, such as gabapentin. Those with kidney failure may need a kidney transplant or dialysis, a procedure to filter the blood. If it is determined that a medication is causing the tremor, the medication may be discontinued or another may be used in its place.
Side effects depend on the treatments used. For example, diazepam may cause sleepiness. Dialysis has many side effects, including infections, salt imbalances, and death.
Individuals with fatigue or drug-related trembling may be cured by treatment. These individuals can usually return to normal activities as soon as they feel able. Those with nervous system damage may be permanently disabled and need help with basic activities, such as eating or getting dressed.
An individual can usually monitor the trembling at home. Changes or responses to therapy can be reported to the healthcare provider. Other monitoring is related to the cause. For example, an individual with high thyroid hormone levels may need repeat thyroid function tests to make sure the level of thyroid hormone returns to normal after treatment.
Author:Adam Brochert, MD
Editor:Slon, Stephanie, BA
Reviewer:Melissa Sanders, PharmD
The Merck Manual, 1995, Berkow et al.