Korlym, also known by its generic name mifepristone, is a cortisol receptor blocker. It's used to manage high blood sugar levels in certain adults with Cushing's syndrome who have Type 2 diabetes. This medication is an option for people if they can't have surgery or if surgery didn't help with their condition. Korlym (mifepristone) is a tablet that's taken by mouth once per day with food. Dosage adjustments are based on how well the medication is working. It also depends on whether you have unpleasant side effects. Common side effects include nausea, fatigue, and headache.
Managing high blood sugar levels in adults with Cushing's syndrome and Type 2 diabetes who can't have surgery or who've already tried surgery
When you have Cushing's syndrome, your body makes too much cortisol. Cortisol is your body's natural "stress hormone." Too much cortisol in the body can cause symptoms like high blood sugar.
Korlym (mifepristone) is a glucocorticoid receptor blocker. It's also known as a cortisol receptor blocker. The medication stops cortisol from attaching to its receptors. This helps lower blood sugar in people with Cushing's syndrome.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Incidence not known
Chest pain or discomfort
confusion
cough or hoarseness
fast, weak pulse
fever or chills
lower back or side pain
pain or discomfort in the arms, jaw, back, or neck
painful or difficult urination
pale, cold, or clammy skin
shortness of breath
sudden increase in stomach or shoulder pain
sweating
unusual or large amount of vaginal bleeding
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Abdominal or stomach pain or uterine cramping
back pain
dizziness
headache
nausea or vomiting
Less common
Acid or sour stomach
belching
fainting or lightheadedness when getting up from a lying or sitting position
flu-like symptoms
headache
increased clear or white vaginal discharge
indigestion
itching of the vagina or genital area
lack or loss of strength
pain during sexual intercourse
pain or tenderness around the eyes and cheekbones
pale skin
shaking chills
stomach discomfort, upset, or pain
stuffy or runny nose
tightness of the chest
trouble sleeping
troubled breathing
troubled breathing, exertional
unusual bleeding or bruising
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
A possible option for people with Cushing's syndrome who can't have surgery or who've had surgery without success
Taken by mouth just once per day
Not a first-choice option because it has many side effects and drug interactions
Not reliable to monitor cortisol levels during treatment
Not safe for people who are pregnant
Take Korlym (mifepristone) at the same time every day. Be sure to take it with food to help your body absorb the medication.
Don't split, crush, or chew the Korlym (mifepristone) tablets. Otherwise, it could affect the way your body absorbs the medication. Contact your prescriber if you're having trouble swallowing Korlym (mifepristone).
Regularly follow up with your prescriber about your treatment with Korlym (mifepristone). Let them know about any symptom improvement or bothersome side effects. Also get any blood tests that your prescriber recommends (for example, for checking blood sugar or insulin levels). This information is helpful for your prescriber in deciding whether you need any dose adjustments.
Avoid drinking grapefruit juice and eating grapefruit while you're taking Korlym (mifepristone). It can raise the levels of the medication in your body and raise your risk for side effects.
Make sure your care team knows about all your prescription and over-the-counter medications. Also, don't start any medications while you're taking Korlym (mifepristone) without asking your care team if it's safe first. Korlym (mifepristone) can interact with many medications. This can affect how well your medications work or put you at higher risk for side effects.
Tell your prescriber if you're taking any steroid medications. Korlym (mifepristone) might block the effects of steroids. This can make the steroid work less well for the condition you're taking it for. Depending on why you need steroids, your care team might consider a different medication for you instead of Korlym (mifepristone).
Use nonhormonal birth control, such as condoms or a spermicide, while you're taking Korlym (mifepristone) if you're sexually active and if you can get pregnant. This medication can make hormonal birth control work less well at preventing pregnancy. It's important to take steps to prevent pregnancy during treatment because Korlym (mifepristone) can cause pregnancy loss.
Korlym (mifepristone) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Korlym (mifepristone) can cause a loss of a pregnancy. To lower the chance of this happening during treatment, you must take a pregnancy test before you start Korlym (mifepristone) if you can become pregnant. You'll also need to take a pregnancy test if you've stopped taking the medication for at least 14 days. You can take the medication once it's confirmed that you're not pregnant.
While you're taking Korlym (mifepristone), you'll need to use a form of nonhormonal birth control (like condoms) if you're sexually active. Continue to use these forms of birth control for at least 1 month after your last dose of Korlym (mifepristone). Don't use hormonal birth control because Korlym (mifepristone) makes it not work as well. This can lead to an unexpected pregnancy. Ask your healthcare professional (HCP) or pharmacist if you have questions about how to prevent pregnancy.
Stop taking Korlym (mifepristone) and tell your HCP right away if you think you're pregnant.
Use a form of nonhormonal birth control, like condoms or Paragard (the copper intrauterine device), while you're taking Korlym (mifepristone) if you're sexually active. Korlym (mifepristone) can make hormonal birth control work less well, which can raise the risk of having an unexpected pregnancy.
It's important to prevent pregnancy while you're taking Korlym (mifepristone) and for a month about treatment ends. This medication can cause pregnancy loss. Stop taking Korlym (mifepristone) and let your prescriber know right away if you think you're pregnant.
People who take Korlym (mifepristone) can develop adrenal insufficiency (when the adrenal gland doesn't make enough of its natural hormones). The medication stops cortisol, one of the hormones that the adrenal gland makes, from working.
Adrenal insufficiency can lead to symptoms like tiredness, weakness, nausea, vomiting, low blood pressure, and low blood sugar levels. Let your care team know right away if you have any symptoms of adrenal insufficiency while you're taking Korlym (mifepristone). You might need to stop Korlym (mifepristone) and get treated with corticosteroids.
Risk factors: Bleeding problems | Taking blood thinners
In addition to being a cortisol receptor blocker, Korlym (mifepristone) is also a progesterone receptor blocker. When the medication blocks the hormone progesterone in the body, it can cause bleeding from the vagina. It can also make the uterus lining thicken.
Let your prescriber know if you have a history of bleeding problems or you're taking any blood thinners. These situations might raise your risk for vaginal bleeding. Contact your prescriber or obstetrician-gynecologist (OB-GYN) if you notice any unusual vaginal bleeding after you start Korlym (mifepristone).
Korlym (mifepristone) can cause low potassium levels at any time during treatment. Your prescriber will check your potassium levels before you start taking Korlym (mifepristone). They'll also check your potassium regularly throughout treatment, such as a few weeks after you start treatment and after your dose gets raised.
Your prescriber might recommend that you take a potassium supplement to raise your levels if you need it. You might need additional medications to help manage this side effect if potassium supplements aren't enough.
Let your prescriber know if you feel symptoms of low potassium, such as muscle aches or cramps, nausea, unusual fatigue, or abnormal heartbeats, while you're taking Korlym (mifepristone).
Risk factors: Taking other medications that cause QT prolongation | Personal or family history of long QT syndrome | History of heart failure or other heart problems | Low potassium or magnesium levels
Korlym (mifepristone) can affect your heart rhythm by lengthening the time it takes for the heart to pump and then relax. This is known as QT prolongation (or long QT syndrome), which can be life-threatening.
Your risk for QT prolongation can be higher in certain situations. Examples include having abnormal electrolyte levels or heart rhythm problems. In addition, you might be at risk if you take other medications that can cause QT prolongation along with Korlym (mifepristone).
To lower your risk for QT prolongation, your prescriber will make sure that you're taking the lowest possible dose of Korlym (mifepristone) that works for you. They might want to check your heart rhythm from time to time.
Call 911 right away if you feel your chest pounding; feel short of breath, faint, or lightheaded; or have chest pain while you're taking Korlym (mifepristone). These can be signs of heart rhythm problems.
Korlym (mifepristone) can interact with many other medications. Some of these drug interactions can raise the levels of mifepristone in the blood, which can put you at risk for side effects. Korlym (mifepristone) can also block the effects of steroids and make them work less well.
Share with your healthcare team an updated list of medications that you take or plan to take with Korlym (mifepristone). Include any prescription medications, over-the-counter products, and herbal supplements.
Your care team can check for drug interactions and weigh any risks and benefits. Your prescriber might need to make changes to your treatment plan to keep to safe. These changes can include stopping certain medications or making dose adjustments.
The typical starting dose is 300 mg by mouth once per day with a meal.
Your prescriber might raise the dose every 2 to 4 weeks based on how well the medication is helping your condition. Your prescriber might also adjust the dose depending on the side effects you have from the medication.
The maximum dose is 1,200 mg by mouth once per day.
Note: Your dose might differ if you have liver problems or kidney problems. In addition, your dose might differ if you're also taking a medication that interacts with Korlym (mifepristone).
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Allergy to mifepristone
Currently pregnant
Unexplained vaginal bleeding
Endometrial thickening that's suggestive of cancer
Take oral or injected corticosteroids for life-saving conditions
Take certain medications that interact with Korlym (mifepristone) and raise the risk for side effects. Examples include simvastatin (Zocor), dihydroergotamine, fentanyl, cyclosporine (Sandimmune), and tacrolimus (Prograf), among others.
Managing high blood sugar levels in adults with Cushing's syndrome and Type 2 diabetes who can't have surgery or who've already tried surgery
High cortisol levels in adults with Cushing's syndrome who already tried surgery or who can't have surgery
Treatment of Cushing's disease in adults who can't receive pituitary gland surgery.
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