Replacing short-acting nifedipine with alternative medications at a large health maintenance organization.

In response to recent evidence about the safety of calcium channel blockers, Group Health Cooperative of Puget Sound (GHC), a large health maintenance organization, implemented a plan in April 1996 to reevaluate the medications of 1349 patients who were taking short-acting nifedipine. Following the intervention, 79.8% of patients taking short-acting nifedipine discontinued use, and 45.6% switched to once-daily felodipine. By presenting physicians and patients with recent evidence about the safety of short-acting nifedipine, a large health maintenance organization was able to motivate broad-scale changes to safer alternative drug therapies.