HONOLULU (CN) – The American Civil Liberties Union of Hawaii filed a federal lawsuit against the Food and Drug Administration over federal restrictions that limit access to an abortion pill.

The abortion pill Mifeprex, also called RU-486, currently cannot be obtained at a retail pharmacy. Instead, a prescription for the pill must be obtained from a clinic, medical office or hospital that has registered with the manufacturer.

In addition, a woman seeking the pill must sign a patient agreement attesting that she has received counseling on the risks associated with Mifeprex, according to a lawsuit filed Tuesday by ACLU attorneys.

The complaint, filed in Hawaii federal court on behalf of a Kauai doctor and several health care providers, claims the FDA subjects Mifeprex to a Risk Evaluation and Mitigation Strategy, or REMS, process that burdens medical providers and limits patient access to the pill.

The FDA imposes restrictions on access to the drug despite its own finding in March 2016 that serious adverse events associated with Mifeprex are “exceedingly rare,” the lawsuit states.

The ACLU says the REMS process violates the U.S. Supreme Court’s 2016 decision in Whole Woman’s Health v. Hellerstedt, which found that health care regulations must serve patient health and cannot limit access to abortion without a valid medical reason.

“The unique and harmful restrictions the FDA imposes on where and how a patient may receive Mifeprex deny women meaningful access to this safe and effective treatment with no medical justification,” the complaint says.

Risks associated with Mifeprex are lower than those of common medications such as Viagra or blood thinners, according to the ACLU, and the risk of fatality is 14 times greater for a woman who carries a pregnancy to term than for a woman who uses Mifeprex.

Since the drug’s approval in 2000, about 3 million women in the United States have used Mifeprex to end an early pregnancy, the complaint states.

Lead plaintiff Dr. Graham Chelius, chief medical officer with the Hawaii Health Systems Corporation on the island of Kauai, laments that he is unable to comply with medically unnecessary requirements. Specifically, he said he is unable to stock the abortion pill on site because of opposition to abortion by co-workers.

According to the ACLU’s lawsuit, because of the Mifeprex REMS, the process for stocking the drug can be delayed or derailed altogether by a single individual with influence over a health care facility’s procurement procedure.

“Because I can’t stock this medication, my patients are forced to fly to a different island, 150 miles away, just to get a pill or any other kind of abortion care,” Chelius said in a blog post, “making this trip is a real challenge for my patients, many of whom don’t have a lot of money.”

Julia Kaye, staff attorney with the ACLU Reproductive Freedom Project, said in a statement that the “abortion pill is safe, effective, and legal.”

“So why is the FDA keeping it locked away from women who need it?” she said. “The FDA’s unique restrictions on medication abortion are not grounded in science — this is just abortion stigma made law.”

The FDA has said it does not comment on pending litigation and confirmed this week that its position on Mifeprex has not changed since the agency issued the new guidelines last year, according to reports.

Chelius and his co-plaintiffs are represented by lead attorney Mateo Caballero with the ACLU of Hawaii.