Essential tremor is a common neurological disorder that affects the hands, head, and voice. It is three times more common than Parkinson's disease. People with essential tremor experience shaking they cannot control. The tremors can occur in any part of the body. Often the tremors interfere in daily activities such as eating and drinking or getting dressed. The tremors can begin in early adulthood and may become worse with age. In most cases, essential tremor runs in families.
The guideline panel reviewed 211 articles to make evidence-based recommendations on the treatment of essential tremor. Although medications can reduce tremor, they did not eliminate them completely in most cases.
"Though the tremors do not completely disappear with treatment, they can be managed, making a huge difference in the daily lives of people with essential tremor," said guideline author Theresa Zesiewicz, MD, an associate professor of neurology at the University of South Florida in Tampa.
Propranolol, long-acting (LA) propranolol, and primidone were each found to significantly reduce limb tremors and are strongly recommended in the guideline. Propranolol is also used to treat high blood pressure. Primidone is an anti-seizure medication. Propranolol and primidone may be used in combination for limb tremor when either drug is insufficient alone. Propranolol is also recommended for head tremors, although not as strongly as it is recommended for limb tremors.
The panel also found supporting evidence for other medications to be considered for limb tremors. Sotalol or atenolol – drugs used to regulate blood pressure – can be used as alternatives to propranolol and primidone. The anti-seizure drugs gabapentin (as monotherapy) and topiramate are also recommended.
"Side effects can accompany each of these medications," said Zesiewicz. "If side effects become too adverse, doctors and patients can discuss other drug options."
There is modest evidence to recommend injections of botulinum toxin A for limb, head, or voice tremors.
Surgery can be recommended if drug therapy is ineffective for limb tremors. Deep brain stimulation was found to have fewer severe complications than thalamotomy, according to the guideline. In deep brain stimulation, an electric probe is placed inside the thalamus which helps block the impulses that cause tremors. A thalamotomy places a lesion on a small part of the thalamus which helps stop the signals that cause tremors.
"The surgical option depends on each patient's circumstances and the risk for complications during and after the procedure," said Zesiewicz.
There is insufficient evidence to recommend deep brain stimulation to treat head or voice tremor. Another type of surgery called gamma knife thalamotomy lacked evidence to be recommended for treatment of essential tremor.
Complete guidelines, a summary for physicians, and a summary for patients and their families are available on June 22 at www.aan.com/professionals/practice/guideline/index.cfm.
The American Academy of Neurology, an association of more than 18,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer's disease, epilepsy, Parkinson's disease, multiple sclerosis, and stroke.
For more information about the American Academy of Neurology, visit www.aan.com.
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Neurology