OBJECTIVE: To report a case of acute pancreatitis in a patient receiving a combination formulation of irbesartan and hydrochlorothiazide (HCTZ). CASE SUMMARY: A 33-year-old white woman developed acute pancreatitis 10 days after starting irbesartan 300 mg and hydrochlorothiazide 12.5 mg for treatment of hypertension. Her symptoms disappeared and serum concentrations of lipase and amylase returned to normal 2 days after irbesartan/HCTZ was discontinued. A search of MEDLINE (1990-September 2002) and the Australian Adverse Drug Reaction Advisory Committee database revealed 1 additional case of pancreatitis associated with irbesartan/HCTZ and 3 cases of pancreatitis associated with losartan. DISCUSSION: An objective causality assessment indicates that it is probable that pancreatitis was caused by the angiotensin II receptor antagonist irbesartan (and the same is probably true for losartan). It is less likely that the hydrochlorothiazide in irbesartan/HCTZ caused pancreatitis in our patient since the dose was lower than that usually associated with thiazide-induced pancreatitis. Angiotensin II receptors are thought to be important in regulation of pancreatic secretion and microcirculation, but the mechanism of pancreatitis induced by angiotensin II receptor antagonists remains unclear. CONCLUSIONS: Clinicians should be aware that irbesartan/HCTZ or losartan may cause acute pancreatitis. If abdominal pain develops, the medication should be discontinued and the patient investigated for acute pancreatitis.
OBJECTIVE: To report a case of acute pancreatitis in a patient receiving a combination formulation of irbesartan and hydrochlorothiazide (HCTZ). CASE SUMMARY: A 33-year-old white woman developed acute pancreatitis 10 days after starting irbesartan 300 mg and hydrochlorothiazide 12.5 mg for treatment of hypertension. Her symptoms disappeared and serum concentrations of lipase and amylase returned to normal 2 days after irbesartan/HCTZ was discontinued. A search of MEDLINE (1990-September 2002) and the Australian Adverse Drug Reaction Advisory Committee database revealed 1 additional case of pancreatitis associated with irbesartan/HCTZ and 3 cases of pancreatitis associated with losartan. DISCUSSION: An objective causality assessment indicates that it is probable that pancreatitis was caused by the angiotensin II receptor antagonist irbesartan (and the same is probably true for losartan). It is less likely that the hydrochlorothiazide in irbesartan/HCTZ caused pancreatitis in our patient since the dose was lower than that usually associated with thiazide-induced pancreatitis. Angiotensin II receptors are thought to be important in regulation of pancreatic secretion and microcirculation, but the mechanism of pancreatitis induced by angiotensin II receptor antagonists remains unclear. CONCLUSIONS: Clinicians should be aware that irbesartan/HCTZ or losartan may cause acute pancreatitis. If abdominal pain develops, the medication should be discontinued and the patient investigated for acute pancreatitis.