Mifepristone

Mifepristone, also known as RU-486, is a medication typically used in combination with misoprostol to bring about an abortion during pregnancy. This combination is 97% effective during the first 63 days of pregnancy. It is also effective in the second trimester of pregnancy. Effectiveness should be verified two weeks after use. It is taken by mouth.adj. Capable of preventing gestation, either by preventing implantation or by causing the uterine lining to shed after implantation. —n. A contragestive drug or agent.Also contragestant, abortion pill. A substance called mifepristone, or RU-486, which was developed by Dr. Etienne Baulieu and the Roussel-Uclaf company. The contragestive blocks progesterone receptors in the endometrium (uterine lining), preventing its buildup by progesterone; hence the uterus cannot sustain a pregnancy. It does not prevent fertilization or implantation, so technically it is an ABORTIFACIENT rather than a contraceptive. Mifepristone, also known as RU-486, is a medication typically used in combination with misoprostol to bring about an abortion during pregnancy. This combination is 97% effective during the first 63 days of pregnancy. It is also effective in the second trimester of pregnancy. Effectiveness should be verified two weeks after use. It is taken by mouth. Common side effects include abdominal pain, feeling tired, and vaginal bleeding. Serious side effects may include heavy vaginal bleeding, bacterial infection, and a malformed baby if the pregnancy does not end. If used, appropriate follow up care needs to be available. Mifepristone is an antiprogestogen. It works by blocking the effects of progesterone, making the cervix easier to open, and promoting contraction of the uterus when exposed to misoprostol. Mifepristone was developed in 1980 and came into use in France in 1987. It became available in the United States in 2000. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. Mifepristone was approved by Health Canada in 2015 and became available in Canada in January 2017. Cost and availability limits access in many parts of the developing world. In the United States it generally costs more than $US 200 for a course of treatment as of 2018, though this may range from $US 110 to $US 360. Mifepristone followed by a prostaglandin analog (misoprostol or gemeprost) is used for medical abortion. Medical organizations have found this combination to be safe and effective. Guidelines from the Royal College of Obstetricians and Gynaecologists describe medical abortion using mifepristone and misoprostol as effective and appropriate at any gestational age. The World Health Organization and the American Congress of Obstetricians and Gynecologists recommend mifepristone followed by misoprostol for first- and second-trimester medical abortion. Mifepristone alone is less effective, resulting in abortion within 1–2 weeks in 8% to 46% of pregnancies. Mifepristone is used for the medical treatment of high blood sugar caused by high cortisol levels in the blood (hypercortisolism) in adults with endogenous Cushing’s syndrome who have type 2 diabetes mellitus or glucose intolerance and have failed surgery or cannot have surgery. Mifepristone at low doses has been used for emergency contraception. It may also be used together with misoprostal for early pregnancy loss. Mifepristone has also been used to treat symptomatic leiomyoma (uterine fibroids). Serious complications with mifepristone are rare with about 0.04%-0.9% requiring hospitalization and 0.05% requiring blood transfusion. Nearly all women using the mifepristone/misoprostol regimen experienced abdominal pain, uterine cramping, and vaginal bleeding or spotting for an average of 9–16 days. For most women, the most severe cramps after use of misoprostol last for less than 6 hours and can generally be managed with ibuprofen. Up to 8% of women experienced some type of bleeding for 30 days or more. Other less common side effects included nausea, vomiting, diarrhea, dizziness, fatigue, and fever. Pelvic inflammatory disease is a very rare but serious complication. Excessive bleeding and incomplete termination of a pregnancy require further intervention by a doctor (such as a repeat dose of misoprostol or a vacuum aspiration). Mifepristone is contraindicated in the presence of adrenal failure, long-term oral corticosteroid therapy (although inhaled and topical steroids are fine), hemorrhagic disorders, inherited porphyria, and hemophilia or anticoagulant use. Women with an intrauterine device in their uterus should remove the IUD prior to medication abortion to avoid unnecessary cramping. Mifepristone is not effective in treating ectopic pregnancy, A postmarketing summary found, of about 1.52 million women who had received mifepristone until April 2011 in the United States, 14 were reported to have died after application. Eight of these cases were associated with sepsis; the other six had various causes such as drug abuse and suspected murder. Other incidents reported to the FDA included 612 nonlethal hospitalizations, 339 blood transfusions, 48 severe infections, and 2,207 (0.15%) adverse events altogether.