Abstract: Objective To analyze one case of hyponatremia caused by omeprazole sodium for injection and its metabolic genotypes with triazole antifungals so as to provide reference for safe use of proton pump inhibitors. Methods The clinical data of an 80-year-old patient with invasive pulmonary aspergillosis was analyzed, and the cause of hyponatremia was investigated. Results The patient's hyponatremia might have been related to omeprazole, an adverse reaction caused by omeprazole sodium. Conclusion The possibility of adverse reactions being caused by proton pump inhibitors should be considered when dealing with refractory hyponatremia in clinical practice. When a patient with slow metabolism for CYP2C19 uses hepatic enzyme inhibitors, proton pump inhibitors should be used with caution.

Key words: omeprazole, injection, voriconazole, isavuconazonium, hyponatremia, proton pump inhibitors, adverse drug reactions