Avodart is a prescription medication used to treat benign prostatic hyperplasia (BPH), also known as enlarged prostate. It works by reducing the size of the prostate. Avodart is part of a class of drugs called 5-alpha-reductase inhibitors.

Other drugs in this class include finasteride (Proscar) and Propecia. The most common side effects of Avodart include:

• decreased libido (sex drive)

• impotence (trouble getting or maintaining an erection)

• decreased ejaculate volume

• breast tenderness or enlargement

• allergic reactions such as skin rash, hives, and swelling of the lips, tongue, or throat.