The effect of a therapeutic lithium level on a stroke-related cerebellar tremor

• Published in: BMJ case reports 2018-01, Vol.2018, p.bcr-2017-222920
• Main Authors: Orleans, Rachel A, Dubin, Marc J, Kast, Kristopher A
• Format: Article
• Language: English
• Subjects: Antidepressive Agents - adverse effects; Bipolar disorder; Bipolar Disorder - drug therapy; Case reports; Cerebellar Diseases - complications; Dose-Response Relationship, Drug; Drug Substitution; Humans; Kinases; Lithium; Lithium Compounds - adverse effects; Male; Mental depression; Myoclonus - chemically induced; Psychotropic drugs; Stroke; Stroke - complications; Tremor - chemically induced; Unexpected Outcome (Positive or Negative) Including Adverse Drug Reactions
• ISSN: 1757-790X; 1757-790X
• DOI: 10.1136/bcr-2017-222920

Lithium is a mood stabiliser used in the treatment of acute mania, bipolar disorder and as augmentation for unipolar major depression. Tremor is a common adverse effect associated with lithium at both therapeutic and toxic serum levels. We present a case of dose-dependent changes in the quality and intensity of a stroke-related, chronic cerebellar tremor with lithium treatment at serum levels within the therapeutic range. On admission, the patient in this case had a baseline fine, postural tremor, which increased in frequency and evolved to include myoclonic jerks once lithium therapy was initiated. Although the patient’s serum lithium level was never in the toxic range, his tremor returned to baseline on reduction of his serum lithium level. This case highlights that a pre-existing, baseline tremor may lower the threshold for developing myoclonus. It also suggests that caution may be warranted with lithium therapy in the setting of known cerebellar disease.