(Reuters) - The Louisiana Senate gave final legislative approval on Thursday to a bill that would make the state the first in the U.S. to reclassify two abortion-inducing drugs as controlled substances that carry the potential for abuse or addiction.

The bill would make unprescribed possession of the abortion pills mifepristone and misoprostol a crime punishable by one to five years in prison and fines of up to $5,000, though pregnant women are expressly exempt from prosecution.

The drug classification provisions were added as an amendment to a larger bill outlawing "coerced criminal abortion by means of fraud," making it a crime for abortion-inducing medication to be administered to an unsuspecting pregnant woman without her consent.

Louisiana already has one of the strictest abortion bans in the nation, prohibiting the voluntary termination of a pregnancy through surgical means or medication except when necessary to protect the life of the mother.

The bill cleared the Louisiana House of Representatives on Tuesday by a 64-29 vote, and won final passage on Thursday in the Senate, 29-7. Republicans control both chambers.

The measure now goes to Governor Jeff Landry, a Republican, who is expected to sign it.

The legislation would redefine the two abortion pills under Louisiana law as Schedule IV drugs, a category of medications considered to carry a potential for abuse and dependency, such as Xanax, Valium or Ambien. If enacted, the bill would make Louisiana the first state in the U.S. to classify abortion medications as controlled substances.

Mifepristone and misoprostol, taken together as a two-drug regimen that allows women to terminate a pregnancy at home, account for more than half of all U.S. abortions.

PILLS HAVE OTHER USES

The drugs are also prescribed for medical purposes other than abortion, including during miscarriages. Misoprostol is also used alone to treat ulcers and to induce labor during childbirth.

Critics of the legislation say reclassifying the drugs could complicate or delay non-abortion use of the medication in rural areas where there are fewer pharmacies and providers that keep controlled substances in stock.

The U.S. Food and Drug Administration, which approved the pills for prescription use more than two decades ago, says extensive research has shown the medication to be safe and effective when taken as directed.

While some states, including Louisiana, require an in-person visit with a prescribing physician to obtain the drugs, other states allow the pills to be dispensed through a pharmacy.

Supporters of the reclassification say it is intended to curtail distribution of the pills for illicit uses, such as coerced medication abortions that the thrust of the bill is aimed at preventing.

The measure's chief sponsor, Senator Thomas Pressly, named the bill for his sister whose then-husband slipped abortion drugs he obtained from Mexico into her drinks, causing her serious health effects and nearly ending her pregnancy. The husband, whom she divorced, was later convicted in a domestic violence case and sentenced to 180 days in jail.

Abortion rights groups decried the legislation as part of a larger Republican-driven effort to criminalize abortion generally.

The bill "will make pregnancy and childbirth even more dangerous in a state that already suffers from the worst maternal health outcomes in the nation, especially for Black women and people in rural areas," said Petrice Sams-Abiodun, a spokesperson for the Gulf Coast branch of Planned Parenthood.

The U.S. Supreme Court in March heard oral arguments in a case involving how mifepristone is prescribed and distributed. In their line of questioning, the justices appeared skeptical about siding with anti-abortion groups on the issue.

(Reporting by Steve Gorman in Los Angeles and Brad Brooks in Longmont, Colorado; Additional reporting by Gabriella Borter in New York; Editing by Leslie Adler)

By Steve Gorman and Brad Brooks