Finasteride (By mouth)
Treats an enlarged prostate (benign prostatic hyperplasia or BPH) in men and causes hair growth in male pattern baldness. It may be used alone or in combination with other medicines such as an alpha-blocker (doxazosin, Cardura®) to treat BPH. This medicine is a 5-alpha-reductase inhibitor.
There may be other brand names for this medicine.
When This Medicine Should Not Be Used
You should not use this medicine if you have had an allergic reaction to finasteride. Women and children should not use this medicine.
How to Use This Medicine
- Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
- You may take this medicine with or without food.
- Take this medicine at the same time each day.
- For hair loss, you may need to take this medicine for 3 months or longer before you see an effect.
- For an enlarged prostate, you may need to take this medicine for up to 6 months to see the full effect.
- This medicine comes with patient instructions. Read and follow these instructions carefully. Ask your doctor or pharmacist if you have any questions.
If a dose is missed:
- If you miss a dose or forget to take your medicine, skip the missed dose and take your next regular dose. Do not use extra medicine to make up for a missed dose.
How to Store and Dispose of This Medicine
- Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
- Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
- Keep all medicine away from children and never share your medicine with anyone.
Drugs and Foods to Avoid
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
Warnings While Using This Medicine
- Women who are pregnant or may become pregnant should avoid handling or touching this medicine. This medicine can get into the body through the skin and may harm an unborn male baby. If any of this medicine gets on the skin of a woman, wash the area immediately with soap and water.
- Make sure your doctor knows if you have liver disease or severe problems urinating.
- This medicine will not cure an enlarged prostate problem or male pattern baldness. Once you stop using this medicine, the prostate will begin to grow again within a few months and any new hair will be lost within 12 months.
- This medicine may cause changes to the breast tissue. Tell your doctor if you have any lumps, pain, tenderness, or an enlargement of the breasts while using this medicine.
- This medicine will not prevent prostate cancer but may increase your risk of developing high-grade prostate cancer. Tell your doctor if you have concerns about this risk.
- This medicine may affect the results of the prostate specific antigen (PSA) test, which may be used to detect prostate cancer. Make sure you tell all of your doctors that you are using this medicine.
- This medicine may cause a decrease in the amount of semen you ejaculate during sex. This will not affect your sperm count or your ability to have children.
- Your doctor will need to check your progress at regular visits while you are using this medicine. Be sure to keep all appointments. Blood tests may be needed to check for unwanted effects.
Possible Side Effects While Using This Medicine
Call your doctor right away if you notice any of these side effects:
- Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
- Breast swelling, pain, or tenderness.
- Lightheadedness, dizziness, or fainting.
- Lumps in the breast or under the arm.
- Pain in the testicles.
- Swelling in your hands, ankles, or feet.
If you notice these less serious side effects, talk with your doctor:
- Decrease in the amount of semen.
- Loss of interest in sex or the ability to have sex (impotence).
- Skin rash.
- Sleepiness or unusual drowsiness.
- Stuffy or runny nose.
- Trouble having or keeping an erection.
If you notice other side effects that you think are caused by this medicine, tell your doctor
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
- Last Reviewed on 06/12/2013
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2013 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
This page was last updated: June 18, 2013