Update on treatment of essential tremor.

OPINION STATEMENT: Essential tremor is one of the most common movement disorders in the world. Although millions of people worldwide are affected by ET, only one medication, propranolol, is approved by the United States Food and Drug Administration to treat it. None of the medications currently used as ET therapy were developed specifically for this purpose, and select antihypertensive and antiepileptic medications remain at the forefront of ET therapy. Propranolol and primidone are considered "effective" agents that treat ET; topiramate, atenolol, and alprazolam are "probably effective", and nimodipine, nadolol, and clonazepam are "possibly effective". Medications that probably do not adequately treat ET include levetiracetam and pregabalin. Gabapentin appears to improve ET when used as monotherapy, but not when used as adjunct therapy. Sotalol has been found to be "probably effective" in treating ET in previous reviews, but it may be associated with arrhythmias and should not be routinely recommended. Botulinum toxin A may reduce limb tremor, but may cause dose dependent weakness. Deep brain stimulation (DBS) of the VIM is used as an alternative to pharmacological therapy of ET in patients who fail to adequately respond to medical therapy. The magnitude of effect from DBS is greater than from medical management, but more severe side effects are possible with surgery. Future treatment options for ET will depend on valid animal models, and a better understanding of its pathophysiology.