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. Cancer
No long-term studies to evaluate the carcinogenic potential of mifepristone have been performed. This is in accord with ICH guidelines, which do not require carcinogenicity testing in nongenotoxic drugs intended for administration for less than six months. Pregnancy
Mifepristone alone results in abortion within 1–2 weeks in 54% to 92% of pregnancies. The effectiveness increases to greater than 90% if misoprostol is given after the mifepristone. There is no evidence that the effects of mifepristone can be reversed, although some anti-abortion groups claim that it can be reversed by giving progesterone. Researchers in the United States initiated a trial of the so-called "reversal" regimen in 2019, but stopped prematurely due to serious safety concerns about using mifepristone without follow-up misoprostol.
While the Fourth Circuit had granted a preliminary injunction to allow this distribution, the Supreme Court of the United States issued a stay order in January 2021 to retain the FDAs rule pending the results of the ongoing litigation.On 16 December 2021, the FDA voluntarily adopted a new rule permanently relaxing the requirement that the pill be obtained in person, allowing it to be sent through the mail. A prescription is still required, so that a doctor can screen for risk factors that would make taking the pill unsafe for the mother. Subsection H
Some drugs are approved by the FDA under subsection H, which has two subparts. The first sets forth ways to rush experimental drugs, such as aggressive HIV and cancer treatments, to market when speedy approval is deemed vital to the health of potential patients. The second part of subsection H applies to drugs that not only must meet restrictions for use due to safety requirements, but also are required to meet postmarketing surveillance to establish that the safety results shown in clinical trials are seconded by use in a much wider population. Until December 2021, Mifepristone was approved under the second part of subsection H. The result is that women could not pick the drug up at a pharmacy, but were required to receive it directly from a doctor.