Lithium intoxication–induced dysgeusia accompanied by glossalgia in a patient receiving lithium carbonate: a case report

BACKGROUND: Lithium carbonate is widely used as a first-line therapeutic agent for the depressive and manic phases of bipolar disorder. Although limb tremors and hypothyroidism are well-known side effects of lithium carbonate, other rare adverse reactions can also occur. CASE PRESENTATION: A 53-year-old Japanese woman diagnosed with lithium intoxication developed dysgeusia and glossalgia during treatment with lithium carbonate. She also showed symptoms of a swaying gait, finger tremors, and dysarthria. All of these symptoms subsided when her blood lithium concentration was reduced to a level below that which induces intoxication. CONCLUSIONS: We present a rare case of lithium carbonate–induced dysgeusia accompanied by glossalgia. Early detection of these symptoms is important in clinical settings because they can be overlooked until patients lose their appetite, which severely impairs their quality of life.