The effectiveness of formulary restriction and preauthorization at an academic medical center.

The impact of formulary restriction and preauthorization (FRPA) on prescribing trends was examined over a 5-year period at an academic medical center. Ordinary least squares regression was used to identify hospital units demonstrating statistically significant trends in prescription of restricted agents. Significant decreases in restricted drug use were seen on 2 of 7 medicine units subject to FRPA, whereas a significant increase was seen in 1 of 4 surgical units subject to FRPA.