Essential tremor is a neurological problem that results in tremors (shakiness), usually of the hands and arms, writes Dr. William Weiner, professor and chairman of neurology at the University of Maryland School of Medicine and director of the school's Parkinson's Disease and Movement Disorders Center.
* There is no known cause for essential tremor, although it sometimes runs in families. The onset of the tremor can be in adolescence or later in life. Most people with essential tremor experience very gradual worsening of the tremor over decades. The most common initial symptom is a slight shaking of the hands when reaching for an object or holding a cup. Essential tremor never begins abruptly as a severe tremor.
* Essential tremor is sometimes confused with Parkinson's disease. In most people, the tremor in the two disorders is completely different. People with essential tremor have their most pronounced symptoms when reaching for things (doctors call this an action or kinetic tremor). In Parkinson's disease, patients develop a resting tremor, which occurs when the hand is not being used. In fact, the resting tremor in Parkinson's disease usually disappears when the patient reaches for an object. Essential tremor is an isolated symptom, meaning that there is no weakness, slowness or stiffness associated with it. Of course, the initial onset of a tremor is a cause for concern and should be evaluated by a doctor.
A person with essential tremor also might develop a slight tremor of the head and voice. Leg tremor can occur, but is rare. If the essential tremor becomes worse, people report handwriting changes - large and scribbly - or trouble eating soup with a spoon, peas on a fork and drinking from a cup.
* Fortunately, there are very good treatment options for essential tremor. Two drugs can be very useful: propanolol, which is called a beta blocker, and primidone, which was first used as an anti-seizure medication. Its usefulness in essential tremor has nothing to do with seizures. Both drugs should be started slowly and at low dose and gradually built up to a dose that works.
* If essential tremor becomes very severe and interferes with eating, writing or dressing and if it does not respond to medication, there is an excellent surgical option called deep brain stimulation (DBS).
In this procedure, a specific area within the brain is identified and with the help of computers and sophisticated electronic equipment, a team of neurosurgeons and neurologists guide a probe to an exact spot and determine if low dose electrical stimulation will stop the tremor. If the tremor is markedly helped, the surgeon makes the probe permanent and it is eventually connected to a power pack in the chest wall (similar to a cardiac pacemaker).