Dutasteride is FDA approved for benign prostatic hyperplasia (BPH), a condition characterized by an enlarged prostate that can lead to urinary problems in men. This medication works by blocking the enzyme 5-alpha-reductase, which plays a role in converting testosterone into dihydrotestosterone (DHT). Since DHT promotes prostate growth, lowering its levels can help reduce prostate size and alleviate symptoms like poor urine flow and frequent urination. Dutasteride is also sometimes used off-label to address male pattern baldness, as elevated DHT levels can contribute to hair loss. It may take a few months for the medication’s full effects to become noticeable.