Evaluation of pharmacists' role in preoperative medication review in a Veterans Affairs Health Care System.

PURPOSE: Use of high-risk medications preoperatively may increase the incidence of postoperative complications. Available literature evaluating pharmacists' role in preoperative medication review is limited, and guidance is not currently available on which patients should have a medication review performed by a pharmacist before surgery. A preoperative rehabilitation pilot project in which clinical pharmacists reviewed medication profiles before scheduled surgeries was developed. This review aimed to evaluate pharmacists' role in reviewing medication profiles preoperatively and to identify specific patient factors that suggest a medication review is warranted. METHODS: This retrospective review utilized the electronic medical records of nonfrail adults undergoing preplanned surgeries enrolled in the pilot project from August 2021 to April 2022. Endpoints were determined using descriptive statistics and regression models. A multivariate analysis was performed evaluating high-risk medications and VIONE (Vital, Important, Optional, Not indicated, and Every medication has an indication) polypharmacy risk score. RESULTS: Forty patients were included, with at least one recommendation made in 83% of chart reviews. Many patients (95%) were taking at least one high-risk medication. Of the high-risk medication classes evaluated independently, only antiplatelets were predictive of pharmacy intervention (P = 0.01). Only high-risk medications were independently predictive of pharmacist intervention (P < 0.01) when multivariate analysis was performed. CONCLUSION: Pharmacists made a recommendation in the majority of medication reviews and were most likely to make a recommendation in patients taking high-risk medications. A larger sample size may provide more insight regarding patient-specific factors warranting a preoperative medication review.

Possible inhibitory effects of terbinafine on aripiprazole metabolism: Two case reports.

Aripiprazole, an atypical antipsychotic, is a metabolic substrate for cytochrome P450 (CYP)3A4 and 2D6. Terbinafine, an antifungal agent used for onychomycosis, is a CYP2D6 inhibitor and could theoretically reduce the metabolism of aripiprazole. However, there are no published reports describing this interaction. We present 2 female patients hospitalized in a psychiatric unit who were both taking aripiprazole 15 mg daily and terbinafine 250 mg daily prior to admission. The first patient was a 58-year-old female who was prescribed aripiprazole and terbinafine concomitantly for approximately 5 months prior to admission. A commercial pharmacogenetic testing platform classified this patient as a normal metabolizer for CYP3A4 and 2D6. The first patient's serum trough aripiprazole concentration at steady-state concentration (Css) was 207.5 ng/mL. The second patient was a 43-year-old female who was taking aripiprazole and terbinafine concomitantly for approximately 2 weeks prior to admission who had a Css aripiprazole concentration of 278.9 ng/mL. Aripiprazole has a wide therapeutic range (100 to 350 ng/mL) and a reference dose-related drug concentration of 11.7 (mean) ± 5.6 (SD) ng/mL/mg/d. Our patients had Css aripiprazole concentrations 18% and 59% higher than guideline-supported dose-related drug concentrations. Through the use of therapeutic drug monitoring, pharmacogenetic data, electronic pharmaceutical claims data, and the Drug Interaction Probability Scale, we suggest terbinafine possibly increases aripiprazole concentrations 18% to 59%. Further reports are needed to confirm these findings prior to using this information in clinical practice.