Finasteride is an antiandrogenic drug that is metabolized in about 1 to 2 days for ages 18 to 60 and in about 2 days for ages 70 and older. Finasteride inhibits the conversion of testosterone to the androgen dihydrotestosterone in peripheral tissues and can be used to treat androgenetic alopecia and benign prostatic hyperplasia in men. The metabolism time of Finasteride in the body is prolonged with age, the drug half-life is about 5~6 hours in 18~60 years old people, and it can be metabolized in about 5 half-lives, i.e., 25~30 hours (about 1~2 days); the drug half-life in people over 70 years old is 8 hours, and it can be metabolized in about 40 hours (about 2 days). Finasteride is contraindicated in women, children and those who are allergic to the components of this drug, and its use may cause adverse reactions such as impotence, decreased libido, ejaculation disorders, breast enlargement, breast swelling and pain. Finasteride should be used under the supervision of a doctor, and if discomfort occurs, seek medical attention.