Dutasteride is an oral drug that is prescribed to men with an enlarged prostate to reduce the production of the hormone DHT. Dutasteride has been shown to improve symptoms in some patients with BPH, including nocturia, daytime urination, and urinary urgency. The capsules are used to take dutasteride as a pill. Dutasteride works by blocking the production of DHT in the body. DHT is a hormone that causes the prostate to grow and, as a result, the bladder to feel uncomfortable and to release urine at night.