Dutasteride (patient information)

Why this medication is prescribed

Dutasteride is used to treat an enlarged prostate (benign prostatic hyperplasia, or BPH). Dutasteride is in a class of medications called 5-alpha reductase inhibitors. It works by blocking the production of a natural substance that enlarges the prostate. This shrinks the prostate, relieves symptoms of BPH, such as frequent and difficult urination, and decreases the chance that surgery will be needed to treat this condition.

How this medication should be used

Dutasteride comes as a capsule to take by mouth. It is usually taken once a day with or without food. To help you remember to take dutasteride, take it around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take dutasteride exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the capsules whole; do not split, chew, or crush them.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Special precautions

Before taking dutasteride:

• tell your doctor and pharmacist if you are allergic to dutasteride, finasteride (Propecia, Proscar), or any other medications.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Be sure to mention any of the following: antifungals such as fluconazole, (Diflucan), itraconazole (Sporanox), and ketoconazole (Nizoral); cimetidine (Tagamet); ciprofloxacin (Cipro); clarithromycin (Biaxin); cyclosporine (Neoral, Sandimmune); danazol (Danocrine); delavirdine (Rescriptor); diltiazem (Cardizem, Dilacor, Tiazac); erythromycin (E.E.S., E-Mycin, Erythrocin); fluoxetine (Prozac, Sarafem); fluvoxamine (Luvox); HIV protease inhibitors such as indinavir (Crixivan) and ritonavir (Norvir); isoniazid (INH, Nydrazid); metronidazole (Flagyl); nefazodone (Serzone); troleandomycin (TAO); verapamil (Calan, Covera, Isoptin, Verelan); and zafirlukast (Accolate). *Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if you have or have ever had liver disease or prostate cancer.
• you should know that dutasteride is for use only in men. Women, especially those who are or may become pregnant, should not handle dutasteride capsules. Touching the contents of the capsules may harm the fetus. Women who accidentally touch leaking capsules should wash the area with soap and water immediately.
• you should know that you should not donate blood while you are taking dutasteride and for 6 months after you stop taking this medication.

Special dietary instructions

Talk to your doctor about drinking grapefruit juice while taking this medicine.

What to do if you forget a dose

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Side effects

Dutasteride may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• inability to have or maintain an erection
• decrease in sex drive
• difficulty ejaculating
• breast tenderness or enlargement

Dutasteride may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

Storage conditions needed for this medication

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

In case of emergency/overdose

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

Other information

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to dutasteride.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking dutasteride.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

Brand names

• Avodart®