SAN DIEGO -- An American woman who spent 18 months in a Mexican prison for carrying medication without a prescription was set free Friday.

San Diego-area Rep. Bob Filner says Dawn Marie Wilson was released from a prison in Dublin in the Bay area at about 5 p.m., 10News reported.

Wilson was first transferred to a prison in El Paso, Texas, and later to the Dublin prison, Filner said. A prison official said she arrived at Dublin on Oct. 13. Officials could not comment on what accounted for the delay in her release from U.S. prisons.

On April 11, 2003, Wilson was driving southbound along the Baja peninsula to Puerto Escondido, where she and long-time partner, Terry Kennedy, live aboard a 45-foot Trimaran.

On the highway in Ensenada, she swerved to dodge a piece of furniture that dropped from a truck in front of her and hit a concrete barrier.

Wilson spent the night with a friend while her Toyota was being repaired.

The next morning, she was walking to the mechanic's shop when Mexican police stopped her, claiming she was hitchhiking, she and Kennedy have said in interviews.

Police found in her bag a three-month supply of Dilantin, a drug prescribed to her for seizures resulting from a horse-riding accident, and diet pills she was delivering to a friend.

Wilson was arrested and jailed because of the large amount of medication and also because she did not have prescriptions.

Since her arrest, dozens of people have fought for Wilson's release and contributed thousands of dollars to the cause.

Filner, who wrote to the U.S. Parole Commission asking for her speedy release, said what helped most was the publicity her case generated.

"My experience with the Mexican authorities is that publicity is the best thing," Filner said. "We tried to get as many news outlets to cover it [as we could]. So the combination of the pressure was what worked. The whole story is so sad."