Drugs and myasthenia gravis. An update.

Myasthenia gravis is a disease of the neuromuscular junction in which normal transmission of the neuron-to-muscle impulse is impaired or prevented by acetylcholine receptor antibodies. Several classes of drugs have been associated with clinical worsening of existing myasthenia gravis, and a small subset of drugs, most notably the antirheumatic agent penicillamine, have been implicated in the pathogenesis of a variant of the disease. Recent case reports and other documented evidence link a number of specific agents with clinical worsening of myasthenia gravis.