Timothy C. Hain, MD Chicago Dizziness and Hearing Page last modified: July 21, 2016
Essential tremor (ET) is a common movement disorder in which a high frequency (typically 5-6 hz) tremor occurs in the hands, variably accompanied by a head and/or vocal tremor. It affects 5% of those aged 65 or over. The tremor ordinarily is abolished by ingestion of alcohol, and is increased by nervousness and medications or situations (e.g. stress) that increase adrenalin levels. ET often runs in families, and is generally not associated with brain lesions.
Unsteadiness is not a prominent part of the essential tremor picture, but occasionally it can accompany the tremor.
Essential tremor is generally easily distinguished from the common tremor of Parkinsonism, which is slower and present at rest. The tremor generally affects the hands, sometimes also the head and voice. It is not present at rest -- when the hands are simply on the knees (for example), there should be no tremor. The tremor is typically seen with the arms extended.
The head tremor is usually a "yes-no" tremor -- that is, the head pitches forward and backward, about 2 times/second.
The voice tremor manifests itself as a "quavery" voice. Sometimes there are other types of voice problems too -- straining or hoarseness. It can be seen with video-stroboscopy.
The good news is that ET is very treatable.
Beta blockers (such as propranolol), benzodiazepines (such as klonopin), and a very low dose of mysoline (50 mg) are all commonly used in treatment.
A small amount of propranolol (such as 20 mg) is sometimes used by public speakers with this tremor. It is taken about 30 minutes prior to the stressful event. Beta-blockers reduce the effects of adrenalin, and may also block muscle spindles. A common dose of propranolol for essential tremor is 60 mg/day.
Benzodiazepines (i.e. drugs resembling Valium including klonazepam and alprazolam) and mysoline increase the effects of GABA (an inhibitory neurotransmitter). Thus the two main types of treatments are somewhat independent. Benzodiazepines are very addictive, and their use needs to be with great caution. Primidone is somewhat effective (Findley et al, 1985). It breaks down into the barbituate phenobarbital, but according to Sasso et al (1991), phenobarbital does not affect hand tremor. We find this inference suspicious and think that phenobarbital is likely the active ingrediant.
Topiramate, a seizure medication, has also been reported to improve ET (Ondo et al, 2006). Unfortunately, the effect was small and very close to the effect of placebo. We see no reasonable role for topiramate in the treatment of ET.
Gabapentin, nimodipine and pregabalin are also occasionally used. We have never seen a successful treatment in our patients.
Of course, one should avoid ingesting substances that increase anxiety or cause agitation -- caffeine should be avoided as well as decongestants containing pseudoephedrine and related substances. Also drugs that increase or cause tremor such as sodium valproate (a seizure medication), or venlafaxine (an antidepressant) should generally be avoided.
ET can be treated with high effectiveness with thalamotomy or deep brain stimulation (Zesiewicz et al, 2005). Each surgical procedure entails risk of serious complication -- including for example personality changes. We have encountered patients who can turn their tremor on or off, using a small box that controls a stimulator. This treatment seems most appropriate for persons who have very severe and disabling tremor, refractory to medication.
Treatment of tremor with Botulinium toxin can work, but the mechanism is through creating weakness.