Merck/Schering-Plough's Vyotrin ad was heavily marketed even as the company delayed releasing a study that called into question the drug's effectiveness. Now it's among several ads pulled from the airwaves amid concerns that prescription drug advertisements can sometimes mislead and are not completely truthful.

"I think the main problem with directed consumer ads is they don't give consumers the information they need to make an informed decision about the drug," said Steven Woloshin, associate professor of medicine and of community and family medicine at Dartmouth Medical School. "They don't give the most fundamental information, which is how well does the drug work?"

Today, lawmakers took aim at drug ads during a Capitol Hill hearing, questioning whether ads for pharmaceutical drugs are marketing or educational tools, or downright deceptions.

"American consumers should not have to rely on the oversight function of Congress to make sure drug companies tell the truth in their advertisements," said Rep. Bart Stupak, D-Mich., chairman of the House Committee on Energy and Commerce panel's Oversight and Investigations Subcommittee.

In 2006, drug companies spent nearly $5 billion on direct ads to consumers, an 80 percent increase over what they were spending in 2002, according to IMS Health. Those efforts pay off: Every dollar spent on direct-to-consumer advertising results in $6 in increased sales, according to the House committee's staff. The increase in money spent on ad campaigns surpasses the increase in money spent on research and development for new drugs in the past decade.

But ads tend to play up the benefits of a drug and play down its risks, according to Ruth S. Day, director of Duke University's Medical Cognition Laboratory.

Day found that 80 percent of people who saw drug ads remembered a drug's benefits, while only 20 percent could recall its side effects. She said ads often provide information about a drug's risks by using a faster speech rate or during visual and auditory distractions.

"There's currently, and has been for a long time, an unfair balance between the presentation of the risks and the benefits of these ads," Day said.

As a result, cardiologist Robert Marshall said it can take time to explain the full story to patients asking about a specific drug they have seen on television.

"We spend a lot of time explaining away why they shouldn't be on certain medications, or at least should be addressing other things that should be as important, like lifestyle, diet, exercise, that make as big or a bigger difference in the long term," Marshall said.

Woloshin said advertisements for the sleep aid Lunesta also painted a less than accurate picture.

"In the case of Lunesta, if I don't take the drug, it's going to take me about 45 minutes to fall asleep on average," Woloshin said. "If I take the drug, it'll take about 30 minutes to fall asleep."

An ad for Pfizer's cholesterol drug, Lipitor, featuring Robert Jarvik, also came under fire recently for giving "misimpressions." Ads for Lipitor and Vytorin were voluntarily taken off the air not long after the panel started investigating direct-to-consumer advertising in January.

James Sage, senior director and team leader for Lipitor at Pfizer Inc., maintained that direct-to-consumer ads "encourage an active partnership between patients and their doctors." Still, he said that "going forward we are committed to making sure there's greater clarity in advertising."

Nancy H. Nielsen, president-elect of the American Medical Association, told lawmakers that the AMA strongly discouraged doctors from appearing in ads because "they don't know the patients they're talking to," and she believes the Food and Drug Administration should be given more authority to preapprove these types of ads.

"It is frankly fairly clear that the majority of what's happening has a marketing effect and not an educational effect," Nielsen said.

According to Marcia G. Crosse, director of health care at the Government Accountability Office, the FDA is not completely effective in regulating the ads.

Though the FDA issues warning letters to those companies it finds to be in violation, Crosse said, "the amount of time it takes to draft and issue letters has continued to lengthen." She said it took the FDA more than six months in 2007 to issue letters.

Last year lawmakers set up a voluntary system that would allow drug companies to pay a fee to have the FDA review ads before they're made public.

The review, to be funded by the industry, would have allowed the FDA to hire enough people to review the ads prior to publication. One hundred drug companies signed up to participate. The voluntary review program would have raised more than $11 million from drug companies for prior review of the ads.

The program never launched because Congress then failed to give the FDA the authority to collect the fees from the drug companies.

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