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Outpatient medication errors are common among patients who have received liver, kidney, and/or pancreas transplants

Transplant patients must take numerous medications on a daily basis, including drugs that suppress their immune system to reduce the likelihood of organ rejection. According to a new study, outpatient medication errors among patients with liver, kidney, and/or pancreas transplants are common, often hidden, and associated with significant adverse events.

Monitoring the safety and efficacy of a medication depends on the assumptions that an appropriate prescription was properly transcribed, that the patient and pharmacist followed instructions, that no restricted payer formulary intervened, and that the patient or a surrogate can accurately report about all of these factors, explains Amy L. Friedman, M.D.

Dr. Friedman and colleagues at the Yale University School of Medicine followed transplant patients from one transplant center at an outpatient clinic for 12 months during 2004 and 2005. The researchers reviewed the patients' expected and actual medication lists. They identified 149 medication errors in 93 patients who were prescribed a mean of 10.9 medications each. Adverse events were associated with 32 percent of errors, including hospitalizations or outpatient invasive procedures that were associated with 13 percent of errors. There were nine episodes of transplant rejection and six failed transplants.

The most common type of medication error was patient error (56 percent), such as missing medication doses, followed by prescription errors (13 percent), medication delivery errors (13 percent), availability errors (10 percent), and reporting errors (8 percent). Rarely did patients intentionally disregard or alter their medication regimen. Rather, in many cases, patients misunderstood the proper way to take their medicine, which should be viewed as an opportunity to improve communication. Finances were linked to 5 percent of errors.

The study was supported by the Agency for Healthcare Research and Quality (HS15038). More details are in "Medication errors in the outpatient setting," by Dr. Friedman, Sarah R. Geoghegan, B.S.N., Noelle M. Sowers, R.N., and others, in the March 2007 Archives of Surgery 142, pp. 278-283.

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