There are a number of potential causes of hand tremors, ranging from medication side effects to benign genetic conditions. Patients who experience problems with tremors may need an evaluation to learn more about why they developed in order to determine which treatment options, if any, are available. Treatments may include changing medications, physical therapy, or treating an underlying medical issue more aggressively. The best option can depend on the patient’s specific case and medical history.
Tremors can be loosely divided into resting, intention, and postural tremors. People experience resting or static tremors when their hands shake if they are not moving, and the intensity lessens as the hands are used. Intention or action tremors occur when people try to do something like writing and their hands start to tremble. Postural tremors occur when the hands are held in a given position for too long; for example, someone might start to shake while carrying a cup across the room.
Environmental factors can be one of the causes of hand tremors. People may experience shaking in connection with fear, anger, anxiety, and other intense emotions. High caffeine or nicotine intake can also be a cause. These tremors should resolve when the patient’s environment returns to normal. Medications are also known causes of hand tremors, especially if they act on the brain or central nervous system.
Conditions involving the brain, like stroke, tumor, and Parkinson's disorder, are also causes of hand tremors. The shaking may be an important diagnostic sign, or could appear after the patient has already been diagnosed. Diseases affecting the central nervous system, like Multiple Sclerosis (MS) are known to cause tremors and instability as well. Hyperthyroid disease is another potential culprit.
Genetics can be a factor in the causes of hand tremors. Some people have a family history of tremor, particularly in the case of benign essential tremor. Shaking is also a normal part of aging; people may notice that their hands start to tremble as they get older. This can be accompanied with a loss of motor control that makes it hard to perform some activities without fumbling.
When patients develop shaking hands, a neurological examination can identify possible causes of tremors. The patient may need to provide a history and take some tests, including medical imaging studies to look at the brain. This information can determine why the shaking started and if treatments are available. Sometimes a simple change like switching psychiatric medications can resolve the issue.