Essential tremor: symptoms and treatment.

Essential tremor (ET), traditionally considered benign, is a serious neurologic condition with life-altering repercussions. Its involuntary, rhythmic oscillations involve alternating, irregular, or simultaneous contractions of agonist and antagonist muscles. It is the most common of the 20 known tremor disorders and often confused with Parkinson's disease. Numerous drugs can aggravate ET, and alcohol consumption may alleviate it. Its etiology is unknown. Proven drug treatments are currently limited to propranolol and primidone. This article reviews ET with examples from history to demonstrate points.