Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Breast cancer: Male breast cancer has been reported in a small number of people taking finasteride. It is not known with certainty whether finasteride can cause breast cancer, but this possibility cannot be ruled out at this time. If you notice any changes in your breasts, such as breast enlargement, pain, tenderness, lumps, or nipple discharge, contact your doctor as soon as possible.
Laboratory tests: This medication may decrease PSA levels (a substance normally produced and used to evaluate prostate cancer) and should be taken into account when evaluating PSA levels.
Liver function: Since finasteride is metabolized in the liver, caution should be used by people with reduced liver function.
Long-term use: The effects of using this medication for the long term (i.e., more than 10 years) have not been established.
Prostate cancer: Finasteride (for BPH) may be linked with an increased risk of developing a rare type of cancer called high-grade prostate cancer. The risk of this cancer while taking this medication is still considered very small. Note that finasteride (for BPH) is not approved to treat prostate cancer. If you have any concerns about this medication, talk to your health care provider.
Surgery: People who are candidates for immediate prostate surgery should not take finasteride.
Pregnancy and birth defects: When absorbed into the system of a pregnant woman, finasteride may cause abnormalities of the genitals in a male baby. Crushed or broken finasteride tablets should not be handled by women who are or may become pregnant because finasteride may be absorbed into their system through the skin.
Children: Finasteride should not be used by children.