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Mifepristone (Korlym)

pronounced as (mi fe' pri stone)


For female patients:

Do not take mifepristone if you are pregnant or plan to become pregnant. Mifepristone can cause loss of the pregnancy. You must have a negative pregnancy test before starting treatment with mifepristone and before beginning treatment again if you stop taking it for more than 14 days. If you can become pregnant, you will need to avoid becoming pregnant during your treatment with mifepristone. You must use acceptable forms of birth control during your treatment and for at least 1 month after your treatment is completed. Your doctor will tell you which forms of birth control are acceptable. If you think you are pregnant, you miss a menstrual period, or you have sex without using birth control while taking mifepristone or within 1 month after your treatment, call your doctor immediately.

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

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with mifepristone and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website ( or the manufacturer's website to obtain the Medication Guide.

Talk to your doctor about the risk(s) of taking mifepristone.

Why is this medication prescribed?

Mifepristone (Korlym) is used to treat hyperglycemia (high blood sugar) in people with a certain type of Cushing's syndrome in which the body makes too much cortisol (a hormone) and who have failed surgery or cannot have surgery to treat this condition. Mifepristone is in a class of medications called cortisol receptor blockers. It works by blocking the activity of cortisol.

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

How should this medicine be used?

Mifepristone comes as a tablet to take by mouth. It is usually taken once a day with a meal. Take mifepristone at 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 mifepristone exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets whole; do not split, chew, or crush them. Tell your doctor or pharmacist if you are not able to swallow the tablets whole.

Your doctor will start you on a low dose of mifepristone and gradually increase your dose, not more often than once every 2 to 4 weeks. If you stop taking mifepristone, call your doctor. Your doctor may have to start you again on the lowest dose of mifepristone and gradually increase your dose.

Mifepristone can control your condition but does not cure it. It may take 6 weeks or longer before you feel the full benefit of mifepristone. Continue to take mifepristone even if you feel well.

Other uses for this medicine

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

What special precautions should I follow?

Before taking mifepristone,

  • tell your doctor if you are allergic to mifepristone, any other medications, or any of the ingredients in mifepristone tablets. Ask your pharmacist or check the manufacturer's patient information for a list of the ingredients.
  • tell your doctor if you are taking any of the following medications or have taken them in the last two weeks: corticosteroids such as betamethasone (Celestone), budesonide (Entocort), cortisone (Cortone), dexamethasone (Decadron, Dexpak, Dexasone, others), fludrocortisone (Floriner), hydrocortisone (Cortef, Hydrocortone), methylprednisolone (Medrol, Meprolone, others), prednisolone (Prelone, others), prednisone (Deltasone, Meticorten, Sterapred, others), and triamcinolone (Aristocort, Azmacort); medications that suppress the immune system such as cyclosporine (Neoral, Sandimmune), sirolimus (Rapamune), and tacrolimus (Prograf); dihydroergotamine (D.H.E. 45, Migranal); ergotamine (Ergomar, in Cafergot, in Migergot); fentanyl (Duragesic); lovastatin (Mevacor); pimozide (Orap); quinidine (Quinidex); and simvastatin (Zocor). Your doctor will probably tell you not to take mifepristone if you are taking one or more of these medications.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or have taken in the last two weeks. Be sure to mention any of the following: anticoagulants ('blood thinners') such as warfarin (Coumadin); antifungals such as itraconazole (Sporanox), ketoconazole (Nizoral), posaconazole (Noxafil), or voriconazole (Vfend); aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn); bupropion (Wellbutrin); ciprofloxacin (Cipro); clarithromycin (Biaxin); conivaptan (Vaprisol); diltiazem (Cardizem); erythromycin (E.E.S., E-Mycin, Erythrocin); fluvastatin (Lescol); hormonal contraceptives such as birth control pills, implants, patches, rings, or injections; medications for hepatitis C such as boceprevir (Victrelis) and telaprevir (Incivek); medications for HIV or AIDS such as amprenavir (Agenerase), atazanavir (Reyataz), efavirenz (Sustiva), fosamprenavir (Lexiva), indinavir (Crixivan), lopinavir and ritonavir combination (Kaletra), nelfinavir (Viracept), ritonavir (Norvir), and saquinavir (Fortovase, Invirase); medications for seizures such as carbamazepine (Tegretol), phenobarbital (Luminal, Solfoton), phenytoin (Dilantin); medications for tuberculosis such as rifabutin (Mycobutin), rifampin (Rifadin, Rimactane, in Rifamate, in Rifater) and rifapentine (Priftin); nefazodone (Serzone); repaglinide (Prandin); telithromycin (Ketek); and verapamil (Calan, Isoptin, others). Many other medications may also interact with mifepristone, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor what herbal products you are taking, especially St. John's Wort.
  • tell your doctor if you have ever had an organ transplant or if you have or ever had thyroid disease. If you are a woman and have not had surgery to remove your uterus, tell your doctor if you have or have ever had unexplained vaginal bleeding, endometrial hyperplasia (overgrowth of the lining of the uterus), or endometrial cancer (cancer of the lining of your uterus). Your doctor will probably tell you not to take mifepristone.
  • tell your doctor if you have or have ever had heart failure, a prolonged QT interval (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death), low potassium in your blood, adrenal insufficiency(condition in which the adrenal glands do not produce enough of certain hormones needed for important body functions), a bleeding disorder, or liver, kidney, or heart disease.
  • tell your doctor if you are breast-feeding.

What special dietary instructions should I follow?

Do not eat grapefruit or drink grapefruit juice while you are taking this medication.

What should I do if I 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.

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:

  • headache
  • vomiting
  • dry mouth
  • diarrhea
  • constipation
  • joint or muscle pain
  • swelling of the hands, feet, ankles, or lower legs
  • rash
  • itching

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

  • nausea
  • loss of appetite
  • dizziness or lightheadedness
  • unusual tiredness or weakness
  • nervousness or irritability
  • shakiness
  • sweating
  • muscle weakness, aches, or cramps
  • rapid, irregular, or pounding heartbeats
  • unexpected vaginal bleeding or spotting
  • shortness of breath

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 ( 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).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( for more information if you do not have access to a take-back program.

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.

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 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?

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

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

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

  • Korlym®
Last Revised - 02/15/2017