Understanding Mifepristone: A Comprehensive Overview
Mifepristone, an FDA-approved abortion drug, is a safe and effective option Discover its mechanism, safety, side effects, usage frequency, and the role of misoprostol
The Supreme Court will be reviewing whether there should be limitations on access to the commonly used abortion drug mifepristone, following requests from the Biden administration and the drug manufacturer. The decision of a federal appeals court, if implemented, would impose restrictions on access to the drug. On the other hand, abortion opponents are urging the Court to declare the initial approval of the drug as illegal. A decision on the new case is expected by July.
Mifepristone was approved by the US Food and Drug Administration many years ago and has been proven to be both safe and effective. Despite this, opponents of abortion have disputed its safety and claim that the FDA did not conduct enough studies to approve it.
In recent months, a federal judge in Texas temporarily halted the approval of the drug, but the US Supreme Court has since intervened, allowing mifepristone to remain available for the time being.
How mifepristone works
Along with misoprostol, mifepristone is one of the drugs used for an abortion via medication, as opposed to surgery.
Mifepristone is marketed under the brand names Mifeprex and Korlym, and its sometimes known as RU 486.
On April 21, 2023, a small group of demonstrators, including Rev. Pat Mahoney, Peggy Nienaber, and Mark Lee Dickson, gathered in front of the U.S. Supreme Court in Washington, DC. Organized by The Stanton Public Policy Center/Purple Sash Revolution, the demonstrators were calling on the Supreme Court to affirm the ruling that suspends the Food and Drug Administration's approval of the abortion pill mifepristone, made by Federal District Court Judge Matthew Kacsmaryk. (Photo by Chip Somodevilla/Getty Images)
Supreme Court to make decision on nationwide restrictions for abortion drug
Mifepristone works by blocking progesterone, a hormone that supports the uterine lining needed for a pregnancy to continue.
Without progesterone, the uterus will expel its contents.
In a medication abortion, mifepristone is taken followed by misoprostol after 24 to 48 hours. This medication helps to empty the uterus through heavy bleeding and muscle contractions.
The medications can be taken within 70 days of the first day of the last period after confirming pregnancy. Research indicates that this method is 99.6% effective in ending a pregnancy.
How safe is mifepristone?
After 23 years of approved use and data from hundreds of studies, mifepristone has been proven to be highly safe and effective. This conclusion is supported by 12 of the country's most respected medical associations, such as the American College of Obstetricians and Gynecologists and the American Medical Association, both of which signed an amicus brief in the Texas case.
Pills of Misoprostol, used to terminate early pregnancies, are pictured in this illustration taken June 20, 2022.
Edgard Garrido/Reuters
Suspension of mifepristone approval wouldnt be the end of medication abortion
This abortion medication combination is accessible in over 60 countries worldwide. Following its approval in the US in 2000, the FDA reports a death rate of 0.0005% - equating to 5 deaths for every 1 million people who utilized mifepristone.
Studies demonstrate that the safety of mifepristone is comparable to that of widely-used over-the-counter pain relievers such as ibuprofen and acetaminophen. CNN's analysis of data indicates that mifepristone is actually safer than many commonly prescribed medications. For instance, the risk of death from penicillin, an antibiotic for bacterial infections like pneumonia, is four times higher than that of mifepristone. Similarly, the risk of death after taking Viagra for erectile dysfunction is nearly 10 times greater than that of mifepristone.
Side effects of mifepristone
Mifepristone usually doesnt have many side effects, doctors say, but as with any drug, there can be short-lived ones.
Potential side effects of mifepristone, as reported by the FDA, can encompass dizziness, weakness, vomiting, headache, diarrhea, nausea, and fever or chills.
The occurrence of major adverse events, such as blood loss, hospitalization, or a significant infection, is extremely rare, affecting less than 0.3% of patients, according to a medical associations' amicus brief.
How often is mifepristone used?
The mifepristone-misoprostol combination is the most common abortion method in the US.
Misoprostol on its own
According to the Guttmacher Institute, a leading research and policy organization dedicated to sexual and reproductive health and supportive of abortion rights, medication abortion made up 53% of all abortions in the United States.
Regardless of the availability of mifepristone, misoprostol can still be used independently for medication abortions. The FDA has only approved misoprostol for the prevention and treatment of gastric ulcers. However, some doctors may use it off-label for abortions and other obstetric or gynecologic purposes, such as inducing labor.
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A review found that among all the studies of individuals who only took misoprostol, approximately 78% experienced complete abortions, and a viable pregnancy was terminated in over 93% of cases. Serious complications requiring a transfusion or hospitalization occurred in only 0.2% of cases, at most.
According to Dr. Melissa L. Wong, an obstetrician/gynecologist and a fellow with Physicians for Reproductive Health, taking misoprostol on its own for an abortion may require a higher dosage for effectiveness and can result in more intense side effects. "Misoprostol still works very well and is very safe," Wong said. "Mifeprestone typically does not cause any side effects as it stops the pregnancy hormone. With misoprostol, some people may tolerate it a bit less because of some side effects like nausea, vomiting, sometimes things like diarrhea or a transient fever. Those are still safe and expected side effects, but they are still uncomfortable for anyone."
Devan Cole and Ariane de Vogue contributed to this report.
