Factors that increase the risk of lithium toxicity include renal insufficiency, overdose, volume depletion, infections, decreased effective circulating volume (cirrhosis, congestive heart failure, and nephrotic syndrome), medication interaction (e.g., diuretics and angiotensin-converting enzyme inhibitor), gastroenteritis, and anorexia.[1,7–9]. Here, ACE is linked to congestive heart failure.