Essential tremor is a common disorder than is characterized by involuntary shaking of the head, jaw, hands or legs. It is estimated that there are 5-10 million affected individuals in the United States. Unfortunately, many patients are incorrectly diagnosed as having Parkinson’s disease when they actually have a form of essential tremor (ET). ET tends to run in families and can have onset anywhere from 20-60. Parkinson’s disease most commonly starts after the age of 60 and is generally thought not to be hereditary. The characteristics of essential tremor and Parkinson related tremor are quite different. Typically the tremor seen in Parkinson’s disease occurs in the hands and is seen with the hand at rest. The tremor has a unique “pill-rolling” quality to it. The Parkinson tremor stops when the individual moves or uses their affected hand. Essential tremor is not present when the affected limb is at rest. When an individual moves their arm or tries to grasp or hold an object, then their tremor becomes apparent. This is most readily seen when trying to write, hold a beverage container or use eating utensils. Writing is affected in both conditions. In essential tremor, the writing becomes jerky with a zig-zag appearance to letters whereas with Parkinson patients, their writing becomes progressively smaller, trailing off into a non-legible line. It is uncommon for Parkinson patients to have head, jaw or leg tremor. These are much more commonly seen in the ET population. Patients with Parkinson’s disease have other clinical features that benign tremor patients do not have.
Treatment for patients with essential tremor (benign tremor, familial tremor) is readily available. Many patients have already discovered that small amounts of an alcoholic beverage will temporarily stop their tremor. Medications used to reduce tremor severity may include primidone, clonazepam, propanolol, mirtazepine or Topamax. All of these medications can be helpful but there is a potential for side effects, as with any treatment. For patients with severe, disabling tremor that is not responsive to medical treatment, surgical treatment with deep brain stimulation can be very effective. This procedure is highly effective in minimizing or completely controlling tremor. It has been approved for use since 1997. This procedure can dramatically improve a patient’s quality of life.
In summary, if you or one of your family is affected by obvious tremor, it is in their best interest to see a movement disorder specialist to get the correct diagnosis and treatment. The treatment and prognosis of essential tremor and Parkinson’s disease is quite different. The medications used for one will not help the other. Significant problems with unwanted side effects can develop if each condition is not treated properly.