Short answer: The Proscar label dose is one 5 mg tablet taken once a day, with or without meals, either alone or together with the alpha-blocker doxazosin. The label says a trial of at least 6 months was generally needed to judge whether symptoms improved. The Patient Information says a forgotten tablet is not made up with an extra one; the next tablet is taken as usual.
This is what the FDA label says. Follow your prescriber. Your prescriber may use a different dose or pace than the label's standard schedule.
What Proscar is approved for: Proscar is a 5α-reductase inhibitor approved for symptomatic benign prostatic hyperplasia (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 (section 1.1). With the alpha-blocker doxazosin, it is approved to lower the risk of BPH symptoms getting worse (section 1.2). It is not approved to prevent prostate cancer (section 1.3), and it is not the hair loss product; that is Propecia, finasteride 1 mg.
Source
PROSCAR (finasteride) tablets, prescribing information and Patient Information. Organon. DailyMed, version published March 31, 2026. DailyMed setid 6f988153-fc74-4ca4-b29a-111f750c4a4b
Proscar is one 5 mg film-coated tablet by mouth once a day, with or without meals (sections 2, 2.1).
For use with doxazosin, the dose is the same: one 5 mg tablet once a day together with the alpha-blocker (section 2.2).
The Patient Information suggests taking it at the same time every day to avoid forgetting. Women who are or may be pregnant should not handle crushed or broken tablets (section 5.3).
The table below is the label's schedule, from the Dosage and Administration section. Numbers are copied exactly; the section is in brackets.
| Item | What the label says |
|---|---|
| Monotherapy | One tablet (5 mg) taken once a day |
| With doxazosin | One tablet (5 mg) taken once a day in combination with the alpha-blocker doxazosin |
| Food | May be administered with or without meals |
| Time to judge benefit | A therapeutic trial of at least 6 months was generally necessary to assess whether a beneficial response in symptom relief had been achieved (section 14.1) |
| Tablet | 5-mg blue, modified apple-shaped, film-coated tablet (section 3) |
A new PSA baseline is set at least six months after starting Proscar and PSA is checked periodically after that. Not taking Proscar as prescribed can also affect PSA results.
Other urinary conditions with similar symptoms are considered before starting. Men with large residual urine volume or severely reduced flow are monitored for blockage.
Caution is used in people with liver function abnormalities, since finasteride is broken down extensively in the liver. No dose change is needed for kidney impairment (section 8.7).
No drug interactions of clinical importance have been identified; antipyrine, digoxin, propranolol, theophylline and warfarin were tested with no clinically meaningful interactions found.
If you forget to take Proscar, do not take an extra tablet. Just take the next tablet as usual.
More on this: missed a dose of Proscar.
In Dose Track you set up Proscar as a protocol with the dose and schedule your prescriber gave you. A protocol can hold dose steps, each with its own dose and length in days or weeks, so a step-up plan like the one on the label can be entered once and the app moves to the next step on its own. Reminders follow the schedule, and every dose is logged with the date and time, so you can see which step you are on and when your last dose was. The app follows what you enter; it does not choose or change a dose.
This page is what the FDA label says, in plain words. It is not medical advice. Follow your prescriber, and ask them or your pharmacist about anything here.