Identification of undocumented over-the-counter medications in an academic nephrology clinic

To explore how accurately over-the-counter (OTC) medications were documented in an academic nephrology clinic and the benefits of using a novel short questionnaire as part of medication reconciliation (MR).

We developed a 3-item tailored questionnaire with questions about use of aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), and proton pump inhibitors (PPIs), which clinical leadership identified as medications of interest. Over the course of 20 days, medical assistants administered the questionnaire to clinic patients immediately after the standard MR. We summarized the rate of inaccurate medication documentation by individual drug and drug class, comparing the standard MR process with the questionnaire. We also calculated diagnostic performance characteristics of the questionnaire. We evaluated the severity of drug-drug interactions between OTC medications discovered using the OTC medication questionnaire and patients' other prescription medications.

Nearly 30% (n = 133 of 450) of the participants had at least 1 inaccurately documented OTC medication after the standard MR. The sensitivity and specificity of the standard MR were 79.2% and 93.5%, respectively, for aspirin; 14.5% and 99.5% for NSAIDs; and 80.4% and 97.3% for PPIs. Medication omissions were resolved in the electronic health record approximately two-thirds of the time using the questionnaire. At least 1 drug-drug interaction (DDI) involving active use of an OTC medication was identified in 9.6% of the patients. Of the DDIs, the most common portended effects were increased nephrotoxicity (52.9%), increased bleeding risk (22.9%), and enhanced antiplatelet activity (7.1%).

Despite the standard MR process, inaccurate documentation of commonly used OTC medications occurred in nearly one-third of outpatients in a nephrology clinic. A brief OTC medication questionnaire may be a scalable and effective strategy to address this problem.