Propecia (Finasteride) Medication Information
Propecia (finasteride) is a prescription medication used to treat male pattern baldness. This medication is not for use in females.
Male pattern baldness is the most common type of baldness in men. Male pattern baldness is usually hereditary and involves changes in testosterone, the male sex hormone. The hair becomes finer, shorter, and thinner. It follows a growth pattern of a receding hairline and creates a U-shaped pattern on the sides of the head.
Propecia (finasteride) works to slow hair loss in male pattern baldness by affecting a type of testosterone linked to balding.
Finasteride is also found in another type of prescription medication (Proscar), which is used to treat symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate. Note that Propecia will not work for BPH because it contains a lower finasteride strength.
Propecia is an oral tablet that comes in one strength: 1 mg.
Propecia is usually taken once daily. Be sure to follow your doctor’s prescribed directions.
Propecia may not be safe for people with the following medical history or conditions:
- History of an allergic reaction to any of the ingredients in Propecia
- Liver problems
Propecia is not for use in women. Women who are pregnant or may become pregnant should not touch crushed or broken Propecia tablets. Handling finasteride, the active ingredient in Propecia tablets, could harm your unborn baby’s development.
Like all medications, Propecia may cause side effects. The most common side effects of Propecia are mild, but severe side effects are also possible.
Common side effects may include:
- Decreased libido (sex drive)
- Erectile dysfunction
- Ejaculation disorder
For more information about the side effects of Propecia, talk with your doctor or pharmacist.
There are no known drug interactions with Propecia (finasteride).
Store Propecia at room temperature between 68°F and 77°F (20°C and 25°C).
- Women who are pregnant or may become pregnant should not touch broken or crushed Propecia tablets due to the potential risk of birth defects. If accidental contact occurs, wash the skin immediately with soap and water.
- You can take Propecia with or without food.
How long will it take for Propecia (finasteride) to work?
Most men notice slowed hair loss after 3 months of taking Propecia. If you don’t see any difference after 3 months or longer, talk to your doctor to discuss whether you should continue this medication.
Will I be able to stop taking Propecia after hair growth occurs?
If you stop Propecia, hair loss may continue. Slowed hair loss will only occur while you’re taking this medication. Within 12 months of stopping Propecia, its effects will go away.
Will Propecia regrow hair I have already lost?
No. Propecia will not cause hair regrowth. It only slows hair loss related to male pattern baldness.
- A.D.A.M. Medical Encyclopedia. Overactive Bladder. Johns Creek, GA: Ebix, Inc; 2019. Overactive Bladder. https://medlineplus.gov/ency/article/001177.htm Accessed January 29, 2021.
- Propecia Prescribing Information. Whitehouse Station, NJ: Merck Sharp & Dohme Corp.; 1997. https://www.merck.com/product/usa/pi_circulars/p/propecia/propecia_pi.pdf Accessed January 29, 2021.
Author: Dr. Patricia Weiser, PharmD
Patricia Weiser, PharmD, is a licensed pharmacist and medical writer. She has clinical experience in community and hospital pharmacy. Patricia is a 2007 graduate of the University of Pittsburgh. She resides in Pennsylvania with her husband and two daughters.
The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.