Drug-induced myoclonus: frequency, mechanisms and management.
Myoclonus is a sudden, abrupt, brief, 'shock-like' involuntary movement caused by muscular contractions ('positive myoclonus') or a sudden brief lapse of muscle contraction in active postural muscles ('negative myoclonus' or 'asterixis'). Various disorders can cause myoclonus including neurodegenerative and systemic metabolic disorders and CNS infections. In addition, myoclonus has been described as an adverse effect of some drugs. Level II evidence is available to indicate that levodopa, cyclic antidepressants and bismuth salts can cause myoclonus, while there is less robust evidence to associate numerous other drugs with the induction of myoclonus. The pharmacological mechanisms responsible for this adverse effect are not well established, although increased serotonergic transmission may be involved in the induction of myoclonus by several drugs. Drug-induced myoclonus usually resolves after withdrawal of the offending drug, but in some cases specific treatments are needed.
Jiménez-Jiménez
Félix Javier
FJ
Department of Medicine - Neurology, Hospital "Príncipe de Asturias", Universidad de Alcalá, Alcalá de Henares, Madrid, SpainNeuro-Magister S.L. Company, Madrid, Spain. fjimenez.hupa@salud.madrid.org
Puertas
Inmaculada
I
de Toledo-Heras
María
M
D000863:Antacids / Q000009:adverse effects; D000928:Antidepressive Agents / Q000009:adverse effects; D000978:Antiparkinson Agents / Q000009:adverse effects; D001729:Bismuth / Q000009:adverse effects; D018492:Dopamine Antagonists / Q000009:adverse effects; D064420:Drug-Related Side Effects and Adverse Reactions; D018682:GABA Agents / Q000494:pharmacology; D006801:Humans; D009207:Myoclonus / Q000139:chemically induced* / Q000209:etiology / Q000628:therapy; D018490:Serotonin Agents / Q000494:pharmacology
D000863:Antacids; D000928:Antidepressive Agents; D000978:Antiparkinson Agents; D018492:Dopamine Antagonists; D018682:GABA Agents; D018490:Serotonin Agents; D001729:Bismuth