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Proscar

Generic name: finasteride (fin AS ter ide)
Brand name: Proscar
Drug class: 5-alpha-reductase inhibitors

Medically reviewed by Sanjai Sinha, MD. Last updated on Oct 11, 2021.

What is Proscar?

Proscar (finasteride) prevents the conversion of testosterone to dihydrotestosterone (DHT) in the body. DHT is involved in the development of benign prostatic hyperplasia (BPH).

Proscar is used to treat symptoms of benign prostatic hyperplasia (BPH) in men with enlarged prostate. Finasteride is for use in men only and should never be taken by a woman or a child.

Proscar may also be used to reduce the risk of a sudden inability to pass urine and the need for surgery related to BPH in men with an enlarged prostate.

Proscar may be used alone or prescribed along with another medicine, an alpha-blocker called doxazosin, to help you better manage your BPH symptoms.

Warnings

Finasteride can be absorbed through the skin and can cause birth defects if a woman is exposed to it during pregnancy. Proscar tablets should not be handled by a woman who is pregnant or who may become pregnant. If a woman accidentally comes into contact with this medication from a broken or crushed tablet, wash the area with soap and water right away.

Before taking Proscar, tell your doctor if you have ever had an allergic reaction to finasteride, or to a similar medicine called dutasteride (Avodart).

Using Proscar may increase your risk of developing prostate cancer. Your doctor will perform tests to make sure you do not have other conditions that would prevent you from safely using this medicine.

Call your doctor at once if you notice any breast lumps, pain, nipple discharge, or other breast changes. These may be signs of male breast cancer.

Before taking this medicine

You should not use Proscar if you are allergic to finasteride.

Using Proscar may increase your risk of developing a serious form of prostate cancer. Ask your doctor about this risk.

To make sure this medicine is safe for you, tell your doctor if you have ever had:

This medicine should never be taken by a woman or a child.

Finasteride can cause birth defects if a woman is exposed to it during pregnancy. A broken Proscar tablet should not be handled by a woman who is pregnant or may become pregnant. The medicine from a broken tablet could be absorbed through the skin.

If a woman accidentally comes into contact with a broken or crushed tablet, wash the area with soap and water right away.

How should I take Proscar?

Take Proscar exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Your doctor will perform tests to make sure Proscar is the right treatment for you.

Take with a full glass of water at the same time each day, with or without food.

Your doctor will need to check your progress on a regular basis. You will need frequent prostate specific antigen (PSA) tests to check for prostate cancer.

Tell your doctor if you stop taking Proscar on a regular basis because this could affect your PSA test results.

Store this medicine at room temperature, away from moisture, heat, and light. Keep the tablets in the original container, tightly closed when not in use.

Dosing information

Usual Adult Dose for Benign Prostatic Hyperplasia:

5 mg orally once a day

Comments:
-Dosing is the same both in monotherapy and in combination therapy.

What happens if I miss a dose?

Skip the missed dose and use your next dose at the regular time. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Proscar?

Do not share this medicine with another person, even if they have the same symptoms you have.

Proscar side effects

Get emergency medical help if you have signs of an allergic reaction to Proscar: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you notice any signs of male breast cancer, such as:

  • breast pain or lumps;

  • nipple discharge; or

  • any other breast changes.

Tell your doctor right away if you have:

  • blood in your semen;

  • pain in your testicles; or

  • depression.

It may be harder for you to get a woman pregnant while you are using finasteride.

Common Proscar side effects may include:

  • decreased interest in sex;

  • trouble getting or keeping an erection;

  • trouble having an orgasm;

  • abnormal ejaculation; or

  • breast swelling or tenderness.

The sexual side effects of finasteride may continue after you stop taking this medicine. Talk to your doctor if you have concerns about these side effects.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Proscar?

Other drugs may interact with finasteride, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all other medicines you use.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Proscar only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.