Darifenacin is used to treat an overactive bladder (a condition in which the bladder muscles contract uncontrollably and cause frequent urination, urgent need to urinate, and inability to control urination). Darifenacin is in a class of medications called antimuscarinics. It works by relaxing the bladder muscles to prevent urgent, frequent, or uncontrolled urination.
Darifenacin comes as an extended-release (long-acting) tablet to take by mouth. It is usually taken once a day with plenty of liquid. This medication may be taken with or without food. Take darifenacin at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take darifenacin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Summary from MedlinePlus.gov, click for more information.