How slowly do you push a 20 mg Cardizem bolus on a person with afib with RVR? My patient was an elderly woman with stable BP but HR up to 150 BPM. I pushed her Cardizem bolus over four minutes and her BP stayed stable, but within ten minutes, her fragile little vein turned bright red and was extremely painful. She had crappy access to begin with and we couldn't get anything but a 22 gauge in a tiny vein. Lots of saline flushing alleviated her symptoms, and we started her drip at ten ml/hr. I looked it up, and most references say to push over two minutes, but my charge nurse said she takes 20 to 25 minutes for a 20 mg bolus! Is that crazy, or did I do it way too fast?