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URL of this page: https://medlineplus.gov/druginfo/meds/a600042.html

Mifepristone (Mifeprex)

pronounced as (mi fe' pri stone)

IMPORTANT WARNING:

Serious or life-threatening vaginal bleeding may occur when a pregnancy is ended by miscarriage or by medical or surgical abortion. It is not known if taking mifepristone increases the risk that you will experience very heavy bleeding. Tell your doctor if you have or have ever had bleeding problems or anemia (less than normal number of red blood cells). Tell your doctor and pharmacist if you are taking medications that may cause bleeding including anticoagulants (blood thinners) such as warfarin (Coumadin, Jantoven); heparin; or other medications to treat or prevent blood clots. If so, your doctor will probably tell you not to take mifepristone. If you experience very heavy vaginal bleeding, such as soaking through two thick full-size sanitary pads every hour for two continuous hours, call your doctor immediately or seek emergency medical care.

Serious or life threatening infections may occur when a pregnancy is ended by miscarriage or by medical or surgical abortion. A small number of patients died due to infections that they developed after they used mifepristone and misoprostol to end their pregnancies. It is not known if mifepristone and/or misoprostol caused these infections or deaths. If you develop a serious infection, you may not have many symptoms and your symptoms may not be very severe. You should call your doctor immediately or get emergency medical treatment if you experience any of the following symptoms: fever greater than 100.4 °F (38 °C) that lasts for more than 4 hours, severe pain or tenderness in the area below the waist, chills, fast heartbeat, or fainting.

You should also call your doctor immediately or get emergency medical treatment if you have general symptoms of illness such as weakness, nausea, vomiting, diarrhea, or feeling sick for more than 24 hours after taking mifepristone even if you do not have a fever or pain in the area below your waist.

Because of the risks of serious complications, mifepristone is available only through a restricted program. A program under called the mifepristone Risk Evaluation and Mitigation Strategies (REMS) Program has been set up for all female patients who are prescribed mifepristone. Your doctor will give you the manufacturer's patient information sheet (Medication Guide) to read before you begin treatment with mifepristone. You can only receive the medication from a doctor or a pharmacy that participates in the program. You will also need to sign a patient agreement before taking mifepristone. Tell your doctor if you have questions about treatment with mifepristone or if you cannot follow the guidelines in the patient agreement.

Talk to your doctor and decide whom to call and what to do in case of an emergency after taking mifepristone. Tell your doctor if you do not think that you will be able to follow this plan or to get medical treatment quickly in an emergency during the first two weeks after you take mifepristone.

Keep all appointments with your doctor. These appointments are necessary to be sure that your pregnancy has ended and that you have not developed serious complications of medical abortion.

Talk to your doctor about the risks of taking mifepristone.

Why is this medication prescribed?

Mifepristone is used in combination with misoprostol (Cytotec) to end an early pregnancy. Early pregnancy means it has been 70 days or less since your last menstrual period began. Mifepristone is in a class of medications called antiprogestational steroids. It works by blocking the activity of progesterone, a substance your body makes to help continue pregnancy.

Mifepristone is also available as another product (Korlym), which is used to control hyperglycemia (high blood sugar) in people with a certain type of Cushing's Syndrome in which the body makes too much of the hormone cortisol. This monograph only gives information about mifepristone (Mifeprex), which is used alone or in combination with another medication to end an early pregnancy. If you are using mifepristone to control hyperglycemia caused by Cushing's syndrome, read the monograph entitled mifepristone (Korlym) that has been written about this product.

How should this medicine be used?

Mifepristone comes as a tablet to take by mouth. You will take one tablet of mifepristone once on the first day. Within 24 to 48 hours after taking mifepristone, you will apply four tablets in total of another medication called misoprostol buccally (between the gum and cheek) by placing two tablets in each cheek pouch for 30 minutes, then swallowing the remaining content with water or another liquid. Make sure that you are in an appropriate location when you take misoprostol because vaginal bleeding, cramps, nausea, and diarrhea usually begins within 2 to 24 hours after taking it but could begin within 2 hours. Vaginal bleeding or spotting usually lasts for 9 to 16 days but can last for 30 days or longer. You must go back to your doctor for an exam or ultrasound 7 to 14 days after taking mifepristone to confirm that the pregnancy has ended and to check the amount of bleeding. Take mifepristone exactly as directed.

Other uses for this medicine

Mifepristone is also sometimes used to end pregnancies when more than 70 days have passed since the woman's last menstrual period; as an emergency contraceptive after unprotected sexual intercourse ('morning-after pill'); to treat a certain type of brain tumor, endometriosis (growth of uterus tissue outside the uterus), or fibroids (noncancerous tumors in the uterus); or to induce labor (to help start the birth process in a pregnant woman). 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 if you are allergic to mifepristone (hives, rash, itching, swelling of the face, eyes, mouth, throat, hands; difficulty breathing or swallowing); misoprostol (Cytotec, in Arthrotec); other prostaglandins such as alprostadil (Caverject, Edex, Muse, others), bimatoprost (Durysta, Latisse, Lumican), carboprost tromethamine (Hemabate), dinoprostone (Cervidil, Prepidil, Prostin E2), epoprostenol (Flolan, Veletri), latanoprost (Iyuzeh, Xalatan, Xelpros, in Rocklatan, others), latanoprostene bunod (Vyzulta), tafluprost (Zioptan), travoprost (Travatan Z), treprostinil (Orenitram, Remodulin, Tyvaso); any other medications, or any of the ingredients in mifepristone tablets. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • Some medications should not be taken with mifepristone. Other medications may cause dosing changes or extra monitoring when taken with mifepristone. Make sure you have discussed any medications you are currently taking or plan to take before starting mifepristone with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking mifepristone, please get the advice of your doctor or pharmacist.
  • The following nonprescription or herbal products may interact with mifepristone: aspirin, St. John's wort. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking mifepristone. Do not start any of these medications while taking mifepristone without discussing it with your healthcare provider.
  • tell your doctor if you have or have ever had an ectopic pregnancy ('tubal pregnancy' or pregnancy outside the uterus), adrenal failure (problems with your adrenal glands), or porphyria (an inherited blood disease that may cause skin or nervous system problems). Your doctor will probably tell you not to take mifepristone. Also, tell your doctor if you have had an intrauterine device (IUD) inserted. It must be removed before you take mifepristone.
  • you should know that it is possible that mifepristone will not end your pregnancy. Your doctor will check to be sure that your pregnancy has ended when you return for your follow-up appointment after you take mifepristone. If you are still pregnant after taking mifepristone, there is a chance that your baby may be born with birth defects. If your pregnancy has not ended completely, your doctor will discuss other options to consider. You may choose to wait, take another dose of misoprostol or have surgery to end the pregnancy. If you take a repeat dose of misoprostol, you must have a follow-up visit with your doctor in 7 days after that dose to be sure that your pregnancy has ended.
  • tell your doctor if you are breastfeeding.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you have taken mifepristone.
  • you should know that after ending a pregnancy with mifepristone, you can become pregnant again right away, even before your period returns. 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.

What special dietary instructions should I follow?

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

What should I do if I forget a dose?

You will only take mifepristone in your doctor's office or clinic, so you do not have to worry about forgetting to take a dose at home.

What side effects can this medication cause?

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

  • vaginal bleeding or spotting
  • cramps
  • pelvic pain
  • vaginal burning, itching, or discharge
  • headache

Some side effects can be serious. If you experience any of the symptoms mentioned in the IMPORTANT WARNING section, call your doctor immediately.

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

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of 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).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

You should get mifepristone only from a certified doctor and use this medication only while under the care of a doctor. You should not buy mifepristone from other sources, such as the internet, because you would bypass important safeguards to protect your health.

Do not let anyone else take your medication.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Mifeprex®

Other names

  • RU-486
Last Revised - 12/15/2023