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Mifepristone Side Effects

For the Consumer

Applies to mifepristone: oral tablet

In addition to its needed effects, some unwanted effects may be caused by mifepristone. In the event that any of these side effects do occur, they may require medical attention.

Severity: Major

You should check with your doctor immediately if any of these side effects occur when 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

Severity: Minor

Some of the side effects that can occur with mifepristone may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

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

General

The most commonly reported adverse reactions were nausea, weakness, fever/chills, vomiting, headache, diarrhea, and dizziness.[Ref]

Cardiovascular

Very common (10% or more): Hypertension (24%)
Uncommon (0.1% to 1%): Hypotension (0.25%), hot flush
Rare (less than 0.1%): Myocardial infarction, induced Adam-Stokes syndrome, superficial thrombophlebitis
Postmarketing reports: Syncope, fainting, loss of consciousness, hypotension (including orthostatic), light-headedness, tachycardia (including racing pulse, heart palpitations, heart pounding)[Ref]

Endocrine

Very common (10% or more): Thyroid function test abnormal (18%) in patients with Cushing syndrome[Ref]

It was reported that of the 42 Cushing syndrome patients with detectable TSH at baseline, eight (19%) had increases in TSH above the normal range, while remaining asymptomatic. The TSH levels returned to normal in most patients when this drug was discontinued at the end of the study.
Adrenal insufficiency was reported in two subjects (4%) in Study 400. The most typical symptoms of adrenal insufficiency were nausea and decreased appetite. Adrenal insufficiency resolved in both cases with interruption of this drug and/or dexamethasone administration.[Ref]

Gastrointestinal

Very common (10% or more): Nausea (48%), vomiting (26%), dry mouth (18%), diarrhea (12%), constipation (10%), gastric discomfort, abdominal pain
Common (1% to 10%): Light or moderate cramping
Rare (less than 0.1%): Gastric bleeding, necrotising pancreatitis
Postmarketing reports: Dyspepsia, gastroesophageal reflux[Ref]

Genitourinary

Heavy bleeding occurs in about 5% of the cases and may require hemostatic curettage in up to 1.4% of the cases.
In clinical trials surgical evacuation was needed in 10% to 12% of women, with some studies reporting a rate as high as 20% to 30%. Bleeding can be prolonged for several days after prostaglandin analog administration and sometimes leads to a decrease in hemoglobin levels.[Ref]

Very common (10% or more): Uterine contractions or cramping (up to 45%) following prostaglandin intake, endometrial hypertrophy (38%), vaginal bleeding, uterine spasm
Common (1% to 10%): Endometritis, pelvic inflammatory disease, heavy uterine bleeding, prolonged post abortion bleeding, spotting, severe hemorrhage, breast tenderness
Uncommon (0.1% to 1%): Uterine rupture after prostaglandin intake (during induction of second trimester termination of pregnancy or labor induction for fetal death in utero during the third trimester), hemorrhagic shock, salpingitis
Rare (less than 0.1%): Hydatiform mole, ectopic pregnancy, amniotic band syndrome, gestational trophoblastic tumor, uteroplacental apoplexy, bilateral adnexal mass, intrauterine adhesion, ovarian cyst rupture, breast abscess, hematosalpinx, uterine rupture
Postmarketing reports: Post-abortal infection (including endometritis, endomyometritis, parametritis, pelvic infection, pelvic inflammatory disease, salpingitis); hematometra, leukorrhea, vaginal hemorrhage, metrorrhagia[Ref]

Hematologic

Very common (10% or more): Blood potassium decreased (34%) in Cushing syndrome patients
Rare (less than 0.1%): Thrombotic thrombocytopenic purpura, thrombocytopenia, induced systemic lupus erythematosus
Postmarketing reports: Anemia[Ref]

Metabolic

In Cushing syndrome patients:
Very common (10% or more): Decreased appetite (20%), anorexia (10%)
Postmarketing reports: Increased triglycerides, hypoglycemia[Ref]

Musculoskeletal

Very common (10% or more): Arthralgia (30%), back pain (16%), myalgia (14%), pain in the extremity (12%)
Rare (less than 0.1%): Limb spasm
Postmarketing reports: Muscular weakness, flank pain, musculoskeletal chest pain[Ref]

Nervous system

Very common (10% or more): Headache (44%), dizziness (22%), somnolence (10%)
Rare (less than 0.1%): Vagal symptoms (hot flushes, dizziness, chills), epilepsy, neurogenic tinnitus[Ref]

Other

Very common (10% or more): Fatigue (48%), peripheral edema (26%), pain (14%), chill, fever
Common (1% to 10%): Fainting
Rare (0.01% to 0.1%): Malaise
Very rare (less than 0.01%): Fatal toxic shock caused by Clostridium sordellii endometritis or Escherichia coli (use of mifepristone followed by non authorized vaginal administration of misoprostol oral tablets)
Postmarketing reports: Asthenia, edema, pitting edema, thirst[Ref]

Psychiatric

Very common (10% or more): Anxiety (10%)
Rare (less than 0.1%): Mania
Postmarketing reports: Insomnia[Ref]

Respiratory

Very common (10% or more): Dyspnea (16%), sinusitis (14%), nasopharyngitis (12%)
Rare (less than 0.1%): Bronchospasm, induced bronchial asthma
Frequency not reported: Shortness of breath[Ref]

Dermatologic

Uncommon (0.1% to 1%): Skin rashes (0.2%), pruritus
Rare (0.01% to 0.1%): Urticaria, erythroderma, erythema nodosum, toxic epidermal necrolysis
Very rare (less than 0.01%): Angioedema[Ref]

Hepatic

Rare (less than 0.1%): Abnormal liver function tests, hepatic failure, hepatorenal failure[Ref]

Hypersensitivity

Rare (less than 0.1%): Anaphylaxis
Postmarketing reports: Allergic reaction (including anaphylaxis, angioedema, hives, rash, itching)[Ref]

Ocular

Rare (less than 0.1%): Ophthalmoplegia, periorbital edema[Ref]

Oncologic

Rare (less than 0.1%): Elevated alpha-feto protein, elevated carcinoembryonic antigen[Ref]

Renal

Rare (less than 0.1%): Renal failure[Ref]

References

1. "Product Information. Mifeprex (mifepristone)" Danco Laboratories, New York, NY.

2. "Product Information. Korlym (mifepristone)." Corcept Therapeutics Incorporated, Menlo Park, CA.

3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

4. Cerner Multum, Inc. "Australian Product Information." O 0

Not all side effects for mifepristone may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.

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