While the fate of mifepristone, also known as the abortion pill, plays out in U.S. courts, health care providers have another drug they can continue to use to offer medication abortion.
Misoprostol is primarily an ulcer medication, but it’s used in conjunction with mifepristone in 98% of all reported medication abortions in the U.S., according to the Guttmacher Institute, a research organization that backs reproductive rights. The combination is “the gold standard for medication abortion in the U.S. and elsewhere,” said Alice Mark, interim medical advisor for the National Abortion Federation.
But misoprostol can also be used on its own to end a pregnancy, and multiple health-care providers have said they’d prescribe it on its own if mifepristone disappears from the market.
Last week U.S. District Judge Matthew Kacsmaryk, appointed by President Donald Trump, issued an order suspending the decades-old approval for mifepristone. Late Wednesday, the 5th U.S. Circuit Court of Appeals partially stayed that ruling.
Under the appeals court order, mifepristone could no longer be prescribed after the seventh week of pregnancy or dispensed by mail. Attorney General Merrick Garland said Thursday that the Biden administration will ask the U.S. Supreme Court to intervene and protect the availability of the drug.
Here’s a look at how misoprostol fits into abortion care in the U.S.
What is misoprostol and what is it used for?
Misoprostol, originally developed in 1973, was first marketed as a treatment for gastrointestinal issues. One of its side effects is that it induces miscarriages and in the late 1980s, women in Brazil with no legal access to abortion began taking it to end pregnancies. It has a two-year shelf life.
Approved in the U.S. to treat stomach ulcers, the drug also causes contractions that empty the uterus. In the U.S., it is often used in combination with mifepristone, which blocks progesterone, a hormone that’s necessary for a pregnancy. Both drugs are also used in miscarriage treatment.
Medication abortion has become increasingly popular in the U.S. because it’s less invasive than surgical abortions and is seen as a more convenient alternative to having a procedure done at a health care clinic. As of 2020 more than 50% of all facility-based abortions were done using pills, up from 24% about a decade earlier.
That number is likely higher now because it’s easier to access by mail and via telemedicine, something that patients are increasingly relying on for abortion care. In April, virtual care accounted for 4% of all abortions; by December it was 11%, according to a report from the Society of Family Planning.
Is it effective?
Patients who take three or more doses of only misoprostol see an 87-93% effectiveness rate at ending a pregnancy without additional treatment, according to an article published online in the Contraception journal.
That’s slightly less effective than terminations that use both mifepristone and misoprostol, data show. When taken together, the two drug combination has an efficacy rate of more than 95% in safely ending pregnancies with no further intervention.
Is it safe?
Much like the standard two-drug protocol, misoprostol-only terminations are “extremely safe,” said Ushma Upadhyay, a public health social scientist at the University of California San Francisco.
In a 2019 review of data from 12,829 patients, 0.7% of patients who ended pregnancies only with misoprostol were hospitalized or received a transfusion. The American College of Obstetricians and Gynecologists says using the misoprostol-only protocol is an acceptable alternative to the two-drug regimen while the World Health Organization recommends its use up to 12 weeks in pregnancy.
What are the side effects?
Misoprostol can cause uterine cramping, nausea and vomiting. Some research suggests that patients are more likely to experience fever, chills and diarrhea than those who use the two-drug regimen. “The overall experience is harder for patients,” Upadhyay said.
Dealing with side effects can be particularly difficult for a growing number of patients who have to travel to get care. The average American now lives 275 miles farther from an abortion facility than before the Supreme Court overturned Roe v. Wade last year.
Is it at risk of being banned?
The Texas ruling only addressed mifepristone, not misoprostol, but advocates question whether anti-abortion activists might target it next. Any future possible efforts to take it off the market would be complicated because the drug has FDA approval as an ulcer treatment. It’s not uncommon for doctors to prescribe medicines for things they weren’t explicitly approved for and there’s no legal precedent for challenging that kind of “off-label” use.
Is misoprostol available?
Misoprostol is available by prescription in most pharmacies, though pharmacists may decline to fill them in places with bans. Some providers, both brick-and-mortar and virtual, are preparing to shift over to that drug if the Texas ruling ultimately takes effect. At least two states, New York and California, have said they will stockpile misoprostol to meet anticipated demand from patients.
“Is that people’s preference?” Mark said. “No, we would like to use the FDA approved medication that we’ve used for the last 23 years, but if that’s legally not an option then we’re prepared to offer them something different.”
