TALLAHASSEE, Fla. (AP) - A new Florida law cracking down on 'pill mills' that dispense powerful prescription painkillers is being challenged in federal court.

A company operating pain clinics in South and central Florida, two doctors and a patient sued the state this week in Tallahassee.

They want a federal judge to block the law before it goes into effect Oct. 1.

The suit alleges the law is discriminatory because it bars patients from getting more than a three-day supply of drugs if they don't have insurance and violates free speech rights by limiting clinic advertising.

Another claim is that various provisions are unconstitutionally vague.

A Department of Health spokeswoman had no immediate comment Friday.