What is Finasteride?

How To Use:

Typically taken as 1 tablet orally once daily, with or without food

Visible effects typically take 3 months or longer

A full assessment of effectiveness should be done after 12 months of continued treatment

Discontinuing the medication may result in reversal of any hair regrowth

Important Safety Note:

This medication must not be handled by individuals who are pregnant or planning to become pregnant due to the risk of fetal harm

Common Brands

Propecia (for male pattern baldness), Proscar (for enlarged prostate)

Drug Class

5-alpha reductase inhibitor

Generic Status

Generic version of Propecia, Proscar

Availability

Prescription only

Finasteride works by binding to and inhibiting 5-alpha reductase, the enzyme responsible for converting testosterone into dihydrotestosterone (DHT). DHT is crucial to healthy fetal development, but high DHT levels in adult men can lead to undesirable effects such as shrinking hair follicles and an enlarged prostate.

To treat male pattern baldness, finasteride reduces DHT levels to slow the process of miniaturizing hair follicles – a precursor to thinning. Finasteride can also help the prostate gland reduce its volume by decreasing DHT levels and, in doing so, relieve pressure on the urinary tract to improve flow and minimize how often you need to urinate.

Dosing finasteride is based on whether the patient is using the drug to treat male pattern baldness or an enlarged prostate. Other factors like age and medical history may come into play.

For hair loss: When treating hair loss, the standard dose for finasteride is 1 milligram (mg) taken daily. Clinical studies suggest taking a higher dose is not more effective, and can also increase the risk of side effects. For enlarged prostate: The standard finasteride dose for treating prostate enlargement is 5 mg daily. Missed dose: If you forget to take your daily finasteride dose, standard guidelines recommend skipping it and waiting until the next day’s dose. “Double dosing” is not advised. Topical application: Rather than taking an oral tablet, some physicians may instead recommend applying compounded topical finasteride solutions directly to the scalp. This can reduce systemic absorption of the drug while reducing DHT levels in a localized area. Results timeline: For most people, finasteride does not produce immediate results. Many wait 3 to 6 months before noticing a reduction in hair loss or an improvement in enlarged prostate symptoms. Providers typically recommend a 12-month dose to evaluate the medication’s peak effectiveness. Note: Dosing information is educational only. Your prescribing physician will determine your specific dose based on your individual health needs. Always follow your healthcare provider’s instructions for exact dosing.

FDA-Approved Uses

Finasteride is FDA-approved for two uses:

Increasing hair growth and preventing further hair loss for men with androgenetic alopecia, or male pattern baldness. Treating symptomatic enlarged prostate, preventing acute urinary retention, and reducing the need for corrective surgery in people with benign prostatic hyperplasia. Off-Label Uses

You may see finasteride prescribed for uses that are not “FDA-approved.” This is a very common and legal practice called “off-label” prescribing, where a doctor uses their clinical judgment to prescribe a drug for a different (but well-researched) purpose.

Common off-label uses for finasteride currently used in clinical research and practice include:

Female pattern hair loss: Finasteride is not FDA-approved to treat pattern hair loss in women, but providers may still prescribe the drug to treat hormonal thinning in post-menopausal women and women who are not of childbearing age. Hirsutism: Finasteride may be used off-label to treat excessive body hair growth in women by reducing the androgenic stimulation of body hair follicles.

Side effects may include fatigue, weakness, and low libido in men. Women who are pregnant or plan to become pregnant must not touch or handle this medication as it can lead to fetal abnormalities.

Keep Away From Pregnant People The medicine inside finasteride tablets absorbs quickly into the skin and has been linked to fetal birth defects. It is advised for pregnant women or those who may become pregnant to never handle crushed or broken finasteride tablets.

Patience Goes a Long Way Most men who take finasteride for hair loss do not see immediate results – in many cases, the drug can take months to reach peak effect. Some people even notice a “shedding” phase before hair regrowth occurs, though this is considered a sign that the drug is working as intended.

Wait to Donate Standard guidelines recommend waiting at least 1 month after your last finasteride dose to donate blood. This prevents blood containing levels of finasteride from being transfused to a pregnant person.

Be Consistent With Dosing It is recommended to take your finasteride dose at the same time each day to ensure consistent levels of the medication in your body.

Give Your Doc a Head’s Up Finasteride can alter the lab results for prostate-specific antigen (PSA) levels during routine health screenings. If you are over the age of 40 or undergoing a prostate exam, be sure to let your doctor know you take the drug.

Compared to other maintenance medications, finasteride has relatively few known interactions.

Always give your doctor and pharmacist a complete list of all your medications, vitamins, and supplements to check for potential interactions.

This information should not be used to decide whether or not to take this medicine or any other medicine. Only a healthcare provider has the knowledge and training to decide which medicines are right for you. This summary does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine’s uses from the patient education materials and is not intended to be comprehensive. This limited summary does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you may receive from your healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please review the entire patient education information you receive with the medication.

These are other medications used for similar conditions. They are not necessarily interchangeable — your provider decides what is appropriate for you.