AUGUSTA – Companies that collect, analyze and sell medical data filed suits Wednesday in federal courts in Maine and Vermont, challenging laws in the two states that make doctors’ prescription-writing habits confidential.

A similar law in New Hampshire, the nation’s first, was overturned in April by U.S. District Judge Paul Barbadoro. That decision, in which Barbadoro cited unconstitutional free speech restrictions, has been appealed to the 1st U.S. Circuit of Court of Appeals in Boston.

Wednesday’s complaints were filed by IMS Health of Norwalk, Conn., Wolters Kluwer Health of Conshohocken, Pa., and Verispan of Yardley, Pa. Their complaints ask the court to block the two states from enforcing their laws, which take effect Jan. 1, 2008.

The complaints say the statutes are unconstitutional. They cite violations of the First Amendment by barring the transfer of lawfully obtained information and the 14th Amendment by impeding interstate commerce.

Maine Attorney General Steven Rowe said the suit targeting the state’s Prescription Privacy Law was not a surprise, given the legal challenge in New Hampshire.

“We will vigorously defend the constitutionality of the law and oppose efforts to have its enforcement enjoined,” said Rowe, who had not seen the complaint. Rowe declined to comment further, saying the assertions made by the plaintiffs would be addressed in court.

The executive director of the Vermont Medical Society, Paul Harrington, said his group “is disappointed that the drug companies are seeking to overturn the law passed in Vermont and Maine.”

“We feel the laws are appropriate in that they keep the physicians’ prescribing information out of the hands of the drug company marketers and curtail the drug companies being able to effectively go into the physicians’ offices, having the prescribing information and tailoring their marketing, knowing what the physician is prescribing,” said Harrington.

The companies say that the information, which they gather from a variety of sources, is used by pharmaceutical and biotechnology companies, medical device manufacturers, governmental agencies and researchers.

“Without the right to publish prescriber-identifiable data, the healthcare community will lose a powerful tool to help monitor the safety of new medications and ensure that patients taking them are not harmed,” says the complaint filed in Maine. It also says the laws go against a national trend toward greater transparency in health care practices.

The protection of patient confidentiality has not been an issue in the legal challenges. But the plaintiffs take issue with what they see as special protections for doctors created by the Maine and Vermont statutes.

Randolph Frankel, IMS vice president for external affairs, said the laws are flawed because they create “an entirely new and special privacy right for physicians,” unlike those afforded other licensed professionals such as lawyers and architects, while impeding public oversight of trends in the health care system.

Maine’s law, one of several passed recently which attempt to address high health care and prescription drug costs, was modified after the ruling in New Hampshire to avoid constitutional flaws. Under an “opt out” provision, drug prescribers can prevent release of information that identifies them.

But the challengers say that provision makes the law worse because it increases the danger that the law will be used to shield poor prescribing practices.

The Vermont legislation, which was also amended after the New Hampshire decision, says physicians can release the information to drug companies if they want.

“When the decision was made that struck down the New Hampshire law, there were several reasons given,” said Vermont state Sen. Mark MacDonald. “We have taken each of those considerations into account and crafted a different law with different language to meet the objections of the court in an effort to protect our citizens and doctors from this unnecessary invasion.”

Referring to drug companies, MacDonald said, “The last thing in the world they want is for citizens to pay the same prices for drugs as the rest of the industrial world, and there’s little they won’t do to achieve that goal.”