title: The clinical heterogeneity of drug-induced myoclonus: an illustrated review.
abstract: A wide variety of drugs can cause myoclonus. To illustrate this, we first discuss two personally observed cases, one presenting with generalized, but facial-predominant, myoclonus that was induced by amantadine; and the other presenting with propriospinal myoclonus triggered by an antibiotic. We then review the literature on drugs that may cause myoclonus, extracting the corresponding clinical phenotype and suggested underlying pathophysiology. The most frequently reported classes of drugs causing myoclonus include opiates, antidepressants, antipsychotics, and antibiotics. The distribution of myoclonus ranges from focal to generalized, even amongst patients using the same drug, which suggests various neuro-anatomical generators. Possible underlying pathophysiological alterations involve serotonin, dopamine, GABA, and glutamate-related processes at various levels of the neuraxis. The high number of cases of drug-induced myoclonus, together with their reported heterogeneous clinical characteristics, underscores the importance of considering drugs as a possible cause of myoclonus, regardless of its clinical characteristics.
authors.affiliation: Department of Neurology 935, Radboud University Medical Center, Donders Institute of Brain, Cognition and Behaviour, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.|Biomedical Signal and Systems Group, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. 217, 7500 AE, Enschede, The Netherlands.
authors.forename: Sabine
authors.identifier: http://orcid.org/0000-0001-8470-3050
authors.initials: S
authors.lastname: Janssen
authors.affiliation: Department of Neurology 935, Radboud University Medical Center, Donders Institute of Brain, Cognition and Behaviour, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Bastiaan R
authors.initials: BR
authors.lastname: Bloem
authors.affiliation: Department of Neurology 935, Radboud University Medical Center, Donders Institute of Brain, Cognition and Behaviour, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands. Bart.vandewarrenburg@radboudumc.nl.
authors.forename: Bart P
authors.initials: BP
authors.lastname: van de Warrenburg
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use; D000978:Antiparkinson Agents / Q000009:adverse effects / Q000627:therapeutic use; D004409:Dyskinesia, Drug-Induced / Q000209:etiology; D004831:Epilepsies, Myoclonic / Q000139:chemically induced / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D009207:Myoclonus / Q000139:chemically induced* / Q000209:etiology; D010300:Parkinson Disease / Q000188:drug therapy; D011014:Pneumonia / Q000188:drug therapy
chemical_list: D000900:Anti-Bacterial Agents; D000978:Antiparkinson Agents
keywords: Drug-induced myoclonus; Myoclonus/phenotype; Myoclonus/physiopathology