What are the pros and cons of taking propecia (finasteride)?

Stops hair loss. Obviously the main reason one would take Propecia (finasteride) is to stop hair loss and even reverse it. The potential side effects are erectile dysfunction, gynecomastia, and in very rare cases, breast cancer. The side effects are generally reversible once you stop taking propecia (finasteride). If you have a family history of breast cancer, discuss this with your doctor before starting propecia (finasteride).