Prozac is the trade name and generic name for finasteride, which is usually taken for a long period of time when it is effective and no significant adverse effects appear. Finasteride is a common medication used in the treatment of prostate hyperplasia and is an androgen inhibitor. It is an androgen inhibitor that reduces the size of the prostate and relieves prostate symptoms by lowering the level of androgens, but its effect is slow and symptoms may rebound after discontinuation. Therefore, it is usually taken for a long period of time if no adverse effects occur. Common adverse reactions after taking Finasteride include erectile dysfunction, decreased libido, retrograde ejaculation, feminization of the male breast, and breast pain. The drug is prohibited for women, children, allergic to the product; in addition, finasteride is mainly metabolized in the liver, liver dysfunction should be used with caution. Specific drug use, please use under the guidance of a regular hospital physician or pharmacist.