Background: Metformin is recommended as initial therapy for most patients with type 2 diabetes mellitus. Its most serious adverse effect, lactic acidosis, is a rare entity with a high mortality rate. Despite well-publicized contraindications, metformin is inappropriately prescribed to many hospitalized patients.
Objective: To determine the efficacy of computer alerts at reducing inappropriate metformin prescribing.
Methods: Retrospective chart review of all hospitalized patients who received an order for metformin, before (n = 144) and after (n = 147) an intervention designed to reduce inappropriate administration. This intervention included 2 "hard-stop" computer alerts that prevented prescribing metformin to patients with renal dysfunction and in critical care or postoperative units; and 2 "soft" alerts that fired when no serum creatinine was available or the patient was in an outpatient surgical unit. Charts were reviewed for the presence of contraindications: renal insufficiency, congestive heart failure, recent myocardial infarction, surgery, or intravenous contrast use within 48 hours of metformin administration.
Results: In the preintervention group there were 47 violations compared with 13 violations in the postintervention group (P < .001). The greatest improvement was in surgical patients (39 violations vs 11, P < .001).
Conclusions: Computer alerts at order entry were effective in decreasing the inappropriate prescribing of metformin in an inpatient setting.