BOSTON – New Hampshire is asking a federal appeals court to overturn a lower court ruling that struck down a law making doctors’ prescription-writing habits confidential.

Drug companies use the prescription information to target particular doctors and tailor sales pitches to each one, a practice known as “detailing.”

Oral arguments in the case were to be heard Wednesday before the 1st U.S. Circuit Court of Appeals in Boston.

New Hampshire Attorney General Kelly Ayotte said the law protects physician prescription information from being used for marketing, thereby protecting doctor-patient relationships and the health and safety of patients while also helping contain health care costs.

Less than a month after the law took effect, IMS Health Inc. of Norwalk, Conn., and Verispan LLC of Yardley, Pa., filed a complaint in U.S. District Court asking a judge to declare it unconstitutional.

The companies, which collect, analyze and sell prescription information, said the law went too far. They argue it violated free speech, endangered public health and impeded research.

A judge struck down the New Hampshire law in April. Last month, a judge in Maine struck down a similar law.