OXYBUTYNIN treats symptoms of an overactive bladder, such as loss of bladder control or frequent need to urinate. It works by relaxing muscles in the bladder. It belongs to a group of medications called antispasmodics. Get Oxytrol for as low as $655.67, which is 20% off the average retail price of $824.02 for the most common version, by using a GoodRx coupon.