An Unexpected Case of Lisinopril-Associated Severe Hyponatremia.

Angiotensin-converting enzyme (ACE) inhibitors are a class of medications that have formed the backbone of hypertension management. Of these medications, lisinopril is one of the most commonly used. While known serious side effects of all ACE inhibitors include angioedema and hyperkalemia, ACE inhibitor-associated hyponatremia has been rarely reported. We present a patient with severe hyponatremia associated with lisinopril use and discuss the link between hyponatremia and ACE inhibitors.