DOXAZOSIN treats the symptoms of an enlarged prostate (benign prostatic hyperplasia). It works by relaxing the muscles in the prostate and bladder, which makes it easier to urinate. It belongs to a group of medications called alpha blockers. Get Cardura XL for as low as $202.39, which is 19% off the average retail price of $249.19 for the most common version, by using a GoodRx coupon.