Finasteride

About Finasteride

Finasteride blocks the enzyme that turns testosterone into dihydrotestosterone (DHT), the hormone behind prostate growth and male pattern hair loss. Its two strengths are separately labeled products. Proscar 5 mg, once a day, is labeled for symptomatic BPH in men with an enlarged prostate, to improve symptoms and lower the risk of acute urinary retention and of surgery such as TURP or prostatectomy, and, with the alpha-blocker doxazosin, to lower the risk that symptoms progress; it is not approved to prevent prostate cancer. MedlinePlus says BPH symptoms may take at least 6 months to improve. Propecia 1 mg, once a day, is labeled for male pattern hair loss in men only; it has not been shown to work on a hairline receding at the temples. Daily use for three months or more is generally needed before a benefit shows, and the label says stopping reverses the effect within 12 months.

There is no boxed warning. Finasteride must not be taken in pregnancy or after an allergic reaction to it. Both labels say 5-alpha reductase inhibitors may increase the risk of high-grade prostate cancer. Finasteride lowers PSA, the blood test used to screen for prostate cancer, so the doctor reading the result needs to know: for Proscar, a new baseline is set at least six months after starting, a single result after six months or more is doubled before it is compared with men not taking it, and any confirmed rise from the low point reached on treatment is evaluated. Side effects include decreased libido, erectile dysfunction, less ejaculate and other ejaculation problems, and breast enlargement or tenderness. Reports since approval include sexual problems that continued after stopping, male infertility or poor semen quality, testicular pain, blood in the semen, male breast cancer, depression and suicidal thoughts. MedlinePlus says new or worsening depression or thoughts of self-harm need a call to the doctor right away, and the label asks men to report breast lumps, pain or nipple discharge promptly.

The film coating prevents contact with the drug during normal handling as long as the tablets are not crushed or broken; a woman who is or may be pregnant and touches crushed or broken tablets should wash the area with soap and water right away. In April 2025, the FDA warned that there is no FDA-approved topical finasteride: compounded topical products have no FDA-approved labeling, the drug is expected to be absorbed through the skin into the bloodstream, it can be transferred to others, specifically women, and most of the reports it reviewed said side effects such as erectile dysfunction, decreased libido, anxiety, depression and suicidal thoughts continued after the product was stopped. Entadfi, a capsule combining finasteride with tadalafil for BPH approved in 2021, is listed as discontinued.

Taking Finasteride

How to take it

One tablet once a day, with or without food, at about the same time each day. Keep taking it unless the prescriber says otherwise: BPH symptoms may take at least 6 months to improve, and hair regrown on finasteride is likely to be lost after stopping.

If you miss a dose

If you forget a dose, do not take an extra tablet; take the next tablet at the usual time. Do not take a double dose.

Storage

At room temperature in a tightly closed container, away from light, excess heat and moisture, out of reach of children. Keep crushed or broken tablets away from anyone who is or may become pregnant.

Interactions to know about

The labels report no drug interactions of clinical importance, and finasteride does not appear to affect the liver enzymes that break down many other medicines. Tell anyone who orders a PSA test that you take it.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Finasteride differs from pharmacy to pharmacy

Generic 5 mg tablets are rated to Proscar and generic 1 mg tablets to Propecia, each from several makers, so quotes for the same strength and quantity differ by each pharmacy’s fee and markup and by whether finasteride is on its flat-price generic list. The two strengths are separate products, and a pharmacist fills the one written.

A prescription that names Proscar or Propecia and blocks substitution is filled with the brand. Compounded topical finasteride is not an FDA-approved drug and has no equivalence rating, so it cannot be swapped for the tablets.

Ways to pay less for Finasteride without insurance

• Ask for a generic, and check that the prescription does not block substitution.
• Ask whether finasteride is on the pharmacy’s flat-price generic list, and compare more than one pharmacy.
• Once you and the prescriber decide to continue, ask for a ninety-day supply.
• If a compounded topical product has been suggested, ask the prescriber whether an FDA-approved tablet would suit you instead.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Finasteride

1. 1.Is my prescription for the 1 mg or the 5 mg tablet, and can a generic be dispensed?
2. 2.How should a pregnant woman in my home handle my tablets?
3. 3.Should the doctor who orders my PSA test know that I take finasteride?
4. 4.Which mood or sexual side effects should I report?

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