Mifepristone Side Effects

It is possible that some side effects of mifepristone may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

For the Consumer

Applies to mifepristone: oral tablet

Along with its needed effects, mifepristone 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 while taking mifepristone:

Less common
  • Excessively heavy vaginal bleeding
  • unusual tiredness or weakness
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 of mifepristone 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
  • diarrhea
  • dizziness
  • headache
  • nausea or vomiting
Less common
  • Acid or sour stomach
  • anxiety
  • belching
  • cough
  • fainting or lightheadedness when getting up from a lying or sitting position
  • fever
  • flu-like symptoms
  • headache
  • heartburn
  • 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
  • shortness of breath or troubled breathing
  • sleeplessness or trouble sleeping
  • stomach discomfort, upset, or pain
  • stuffy or runny nose
  • tightness of the chest or wheezing
  • troubled breathing, exertional
  • unusual bleeding or bruising

For Healthcare Professionals

Applies to mifepristone: oral tablet


Hematologic side effects have included anemia and a decrease in hemoglobin of greater than 2 g/dL in 2% of patients.


Genitourinary side effects have included uterine cramping (83%), uterine hemorrhage (9%), vaginitis (3%), leukorrhea (2%), and pelvic pain (2%). Postmarketing reports have included postabortion infection (including endometritis and parametritis) and ruptured ectopic pregnancy. Additional postmarketing reports have included pelvic infection and hematometra. Additional side effects in patients with Cushing syndrome included endometrial hypertrophy.


Gastrointestinal side effects have included abdominal pain (96%), nausea (43% to 61%), vomiting (2% to 31%), diarrhea (18% to 26%), and dyspepsia (3%). Additional side effects in patients with Cushing syndrome included decreased appetite, dry mouth, and constipation.

Nervous system

Nervous system side effects have included headache (2% to 31%), dizziness (1% to 12%), fatigue (10%), insomnia (3%), asthenia (3%), and fainting (2%). Postmarketing reports have included reports of light headedness and loss of consciousness. Additional side effects in patients with Cushing syndrome included somnolence.


Musculoskeletal side effects have included back pain (9%) and leg pain (2%). Additional side effects in patients with Cushing syndrome included arthralgia, myalgia, and pain in extremity.


Immunologic side effects have included fever (4%) and viral infections (4%).


Psychiatric side effects have included increased anxiety (2%).


Cardiovascular side effects have included syncope (1%). Postmarketing reports have included tachycardia (including racing pulse, heart palpitations, and pounding heart. Hypotension, including orthostatic hypotension, has also reported in after marketing use. Additional side effects in patients with Cushing syndrome included hypertension and peripheral edema.


Respiratory side effects have included sinusitis (2%). Additional side effects in patients with Cushing syndrome included nasopharyngitis and dyspnea.


Hypersensitivity side effects have included shortness of breath, rash, hives and itching.


General side effects in patients with Cushing syndrome included pain and fatigue.

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