Hypertrophic cardiomyopathy and nephrogenic diabetes insipidus associated with chronic lithium carbonate use

•Lithium carbonate is an effective mood stabilizer.•We treated a patient for hypertrophic cardiomyopathy.•Her pathology was due to chronic unsupervised lithium carbonate use.•psychiatric patients treated with lithium carbonate should be closely monitored for CV disease. Lithium carbonate is an effective mood stabilizer. We treated a patient for hypertrophic cardiomyopathy due to chronic unsupervised lithium carbonate use. We noted: a) a previously normal ECG; b) the absence of any familiarity for sudden cardiac death; c) the associated nephrogenic diabetes insipidus; d) probable exaggerated lithium plasma concentrations, which had not been monitored over the past few years; and e) the unusual traits of the right ventricle. We would like to stress the need for regular cardiologic follow-up in psychiatric patients treated with lithium carbonate, to minimize its potential cardiac untoward consequences.