What is this medication?

FINASTERIDE (fi NAS teer ide) treats the symptoms of an enlarged prostate (benign prostatic hyperplasia). It works by decreasing the size of the prostate. It belongs to a group of medications called 5-alpha reductase inhibitors.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Proscar

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Liver disease
  • An unusual or allergic reaction to finasteride, other medications, foods, dyes, or preservatives
  • Pregnant or trying to get pregnant
  • Breast-feeding

How should I use this medication?

Take this medication by mouth with water. Take it as directed on the prescription label at the same time every day. You can take it with or without food. If it upsets your stomach, take it with food. Keep taking it unless your care team tells you to stop.

Talk to your care team about the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medication?

  • Saw palmetto or other dietary supplements

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Visit your care team for regular checks on your progress. It may be some time before you see the benefit from this medication.

You may need blood work while you are taking this medication. For example, your care team may have you take a blood test called PSA for the screening of prostate cancer. Make sure your care team knows you are taking this medication before you take a PSA test.

Talk to your care team about your risk of cancer. You may be more at risk for certain types of cancer if you take this medication.

Do not donate blood while you are taking this medication. This will prevent giving this medication to a pregnant female through a blood transfusion. Ask your care team when it is safe to donate blood after you stop taking this medication.

Women who are pregnant or may get pregnant must not handle broken or crushed finasteride tablets. The active ingredient could harm the unborn baby. If a pregnant woman comes into contact with broken or crushed tablets she should check with her care team. Exposure to whole tablets is not expected to cause harm as long as they are not swallowed.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • Breast tissue changes, new lumps, redness, pain, or discharge from the nipple

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

  • Breast pain or tenderness
  • Change in sex drive or performance

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children and pets.

Store at room temperature below 30 degrees C (86 degrees F). Protect from light. Keep the container tightly closed. Get rid of any unused medication after the expiration date.

To get rid of medications that are no longer needed or have expired:

  • Take the medication to a medication take-back program. Check with your pharmacy or law enforcement to find a location.
  • If you cannot return the medication, ask your pharmacist or care team how to get rid of this medication safely.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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