Hyperkalemia associated with ACE inhibitor or ARB plus trimethoprim-sulfamethoxazole

January 01, 0001

Hyperkalemia associated with ACE inhibitor or ARB plus trimethoprim-sulfamethoxazole

The objective of this study by Canadian authors was to characterize the risk of hyperkalemia-associated hospitalization in elderly patients who were being treated with trimethoprim-sulfamethoxazole along with either an angiotensin converting enzyme inhibitor (ACEI) or an angiotensin receptor blocker (ARB). They conducted a population-based, nested case-control study of a cohort of elderly patients 66 years or older who were residents of Ontario, Canada, and who were receiving continuous therapy with either an ACEI or an ARB. Case patients were those with a hyperkalemia-associated hospitalization within 14 days of receiving a prescription for trimethoprim- sulfamethoxazole, amoxicillin, ciprofloxacin, norfloxacin, or nitrofurantoin. For each case, we identified up to 4 control patients from the same cohort matched for age, sex, and presence or absence of chronic renal disease and diabetes. Odds ratios were determined for the association between hyperkalemia- associated hospitalization and previous antibiotic use.

They found: "During the 14-year study period, we identified 4148 admissions involving hyperkalemia, 371 of which occurred within 14 days of antibiotic exposure. Compared with amoxicillin, the use of trimethoprim- sulfamethoxazole was associated with a nearly 7-fold increased risk of hyperkalemia-associated hospitalization (adjusted odds ratio, 6.7). No such risk was found with the use of comparator antibiotics."

The authors concluded: "Among older patients treated with ACEIs or ARBs, the use of trimethoprim-sulfamethoxazole is associated with a major increase in the risk of hyperkalemia-associated hospitalization relative to other antibiotics. Alternate antibiotic therapy should be considered in these patients when clinically appropriate."

A combination of commonly prescribed drugs to be avoided.

For the full abstract, click here.

Arch Intern Med 170(12):1045-1049, 28 June 2010 © 2010 to the American Medical Association
Trimethoprim-Sulfamethoxazole-Induced Hyperkalemia in Patients Receiving Inhibitors of the Renin-Angiotensin System-A Population- Based Study. Tony Antoniou, Tara Gomes, David N. Juurlink, et al. Correspondence to Dr. Antoniou: [email protected]

Category: T. Endocrine/Metabolic/Nutritional. Keywords: angiotensin converting enzyme inhibitor, ACEI, angiotensin receptor blocker, ARB, antibiotics, trimethoprim-sulfamethoxazole, hyperkalemia, hospitalization, nested case-control study, journal watch.
Synopsis edited by Dr Linda French, Toledo, Ohio. Posted on Global Family Doctor 20 July 2010

Pearls are an independent product of the Cochrane primary care group and are meant for educational use and not to guide clinical care.