Off-label drug prescription pattern and related adverse drug reactions in the medical intensive care unit

Abstract

Introduction: The utilization of prescription drugs as off-label is common. While this practice can be beneficial to some patients, it can raise a safety concern when scientific evidence is lacking; hence, this study was conducted to evaluate the off-label drug consumption and its adverse drug reactions (ADRs) in the medical intensive care unit (ICU). Materials and methods: In the prospective cohort study conducted for a duration of 6 months, data pertaining to ICU patients’ (age ≥18 years) demography, diagnosis, treatment, and laboratory investigation were collected to assess for off-label use as well as the strength of evidence and the occurrence of ADRs by using MICROMEDEX 2017 version (Healthcare Series Thomson Reuter, Greenwood, CO). Results: Of total 3574 drugs prescribed, 1453 (41%) were off-label indications and 65 (1.81%) were off-label dose. On the evaluation of off-label indication use, 1279 (88%) were evidence-based and 174 (12%) were low/no evidence-based medications (EBMs); 59 (91%) were evidence-based and 6 (9%) were low/no EBMs for off-label dose. Most commonly prescribed evidence-based off-label drug belonged to the gastrointestinal class while low/no evidence drugs were mostly of anti-infective class. A total of 383 ADRs were identified and 139 (36.2%) were implicated due to off-label medications, of which ADRs with evidence off-label medications (87.8%) were higher than low/no evidence off-label medication (12.2%) (P < 0.001). Conclusions: Widespread presence of off-label use was observed in medical ICU. Although incidence of ADRs was similar to the FDA-approved use, ongoing monitoring of such practice is needed.