MedlinePlus Drug Information: Mifepristone

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Other drug names:	A-Am An-Az B C-Ch Ci-Cz D-Dh Di-Dz E F G H I-J K-L M-Mh Mi-Mz N-Nh Ni-Nz O P-Pl Pm-Pz Q-R S-Sn So-Sz T-To Tp-Tz U-V W-Z 0-9

Mifepristone

(mi fe' pri stone)

Brand name(s): Mifeprex; RU-486

Contents of this page:
Why is this medication prescribed? How should this medicine be used? Other uses for this medicine What special precautions should I follow? What special dietary instructions should I follow?	What should I do if I forget a dose? What side effects can this medication cause? What storage conditions are needed for this medicine? In case of emergency/overdose What other information should I know?

IMPORTANT WARNING:

In a small number of patients, mifepristone may not end pregnancy. If this happens, you may need surgery to end your pregnancy.Mifepristone may cause very heavy vaginal bleeding and other severe side effects. Talk to your doctor and decide what to do and whom to call in case of an emergency after taking mifepristone.Make sure to read the Medication Guide and sign the Patient Agreement before taking mifepristone.

Why is this medication prescribed?

Mifepristone is used alone or in combination with misoprostol to end an early pregnancy. Early pregnancy means it has been 49 days or less since your last period began. Mifepristone is an antiprogestational steroid. It works by blocking the activity of progesterone, a substance that your body produces to help continue a pregnancy.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Mifepristone comes as a tablet to take by mouth. It should be taken only in a clinic, medical office, or hospital under the supervision of a doctor. You will take three tablets of mifepristone on the first day. Two days later you must go back to your doctor. If your doctor cannot confirm that your pregnancy has ended, you will take two tablets of another medication, called misoprostol. You may continue to experience vaginal bleeding for 9 to 30 days or even longer. If your bleeding is heavy, you should call the emergency contact number or your doctor. Fourteen days after taking the mifepristone, you must go back to your doctor for an examination or ultrasound to make sure that the pregnancy has ended.

Other uses for this medicine

Mifepristone also is used occasionally as a 'morning-after pill,' to end an early pregnancy that your doctor already knows will not produce a live baby, and to treat tumors of the meninges (unresectable meningioma), endometriosis, or Cushing's syndrome. Talk to your doctor about the possible risks of using this drug for your condition.

What special precautions should I follow?

Before taking mifepristone,

tell your doctor and pharmacist if you are allergic to mifepristone, misoprostol (Cytotec), carboprost tromethamine (Hemabate), dinoprostone (Cervidil, Prepidil, Prostin E2), epoprostenol (Flolan), latanoprost (Xalatan), other prostaglandins, or any other drugs.
tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially anticoagulants ('blood thinners') such as warfarin (Coumadin), betamethasone (Celestone), carbamazepine (Carbatrol, Epitol, Tegretol), cortisone acetate (Cortone), dexamethasone (Decadron, Dexasone L.A., Dexone, Hexadrol, others), erythromycin (E-Base, E.E.S., E-Mycin, PCE, others), hydrocortisone (Cortef, Cortenema, Hydrocortone), itraconazole (Sporanox), ketoconazole (Nizoral), methylprednisolone (Medrol, others), phenobarbital (Barbita, Luminal, Solfoton), phenytoin (Dilantin, Diphenylan Sodium), prednisolone (Delta-Cortef, Prelone), prednisone (Deltasone, Meticorten, Sterapred, others), rifampin (Rifadin, Rifamate, Rifater, Rimactane), and triamcinolone (Aristocort, Kenacort), and other vitamins and herbal products.
tell your doctor if you have or have ever had adrenal failure; a pregnancy outside the uterus (ectopic pregnancy); bleeding problems; high blood pressure; heart, liver, lung, or kidney disease; diabetes; or severe anemia.
tell your doctor if you have an intrauterine device (IUD) in place. It must be taken out before you take mifepristone.
tell your doctor if you are breast-feeding. You may need to stop using your breast milk for a few days.
if you are having surgery, including dental surgery, tell your doctor or dentist that you are taking mifepristone.
tell your doctor if you smoke ten or more cigarettes a day.
tell your doctor if you do not have adequate access to a medical facility equipped to provide emergency treatment.

What special dietary instructions should I follow?

Do not take this medication with grapefruit juice.

What should I do if I forget a dose?

You will only take mifepristone in your doctor's office or clinic, so you don't have to worry about forgeting to take a dose at home. Make sure you keep all appointments with your doctor.

What side effects can this medication cause?

Side effects from mifepristone can occur. Tell your doctor if any of these symptoms are severe or do not go away:

cramps
vaginal bleeding (for up to 30 days)
upset stomach
headache
vomiting
diarrhea
dizziness
weakness
pelvic pain
fainting

If you experience the following symptom, call your doctor immediately:

vaginal bleeding heavy enough to soak through two thick full-size sanitary pads an hour for 2 hours

What storage conditions are needed for this medicine?

You will only take mifepristone in your doctor's office or clinic, so you will not be storing it at home.

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.

What other information should I know?

If mifepristone treatment does not end your pregnancy and you do not have surgery to end the pregnancy, there is a risk of birth defects in the baby.

After ending this pregnancy with mifepristone, you can become pregnant again right away. If you do not want to become pregnant again, you should begin using birth control as soon as this pregnancy ends or before you start having sexual intercourse again.

You must keep appointments with your doctor 2 days and 14 days after taking mifepristone to make sure that the pregnancy has ended.

Last Revised - 01/01/2003

American Society of Health-System Pharmacists, Inc. Disclaimer