It's a sunny day. Joan Lunden is walking in a field of flowers that would make anyone with hay fever clog up. But it's OK. The camera comes in for a close-up. She's smiling. She takes Claritin.

A young man laments his thinning hair. It runs in the family. But it's OK. He takes Propecia.

Time was, people pretty much kept their medical problems to themselves, and most people didn't know the names of the medicines they took. Their doctor prescribed something for them and they took it. Not anymore. Turn on any morning show, afternoon talk show or the news on CNN and at the commercial breaks you're likely to get a pitch for some prescription drug from one of the nation's pharmaceutical manufacturers.

It's called DTC advertising: direct-to-consumer. "The No. 1 story in health advertising is this boom in DTC advertising," says David Goetzl, who has followed this phenomenon for Ad Age magazine. According to IMS Health, a London-based analyst, pharmaceutical companies in the United States spent $529 million on such television advertising for the first half of 1999, a 68 percent increase in spending over the same time in 1998.

Claritin, medicine for controlling allergies, is the mother of all of this advertising. It was the top-spending brand for TV advertising at $48 million. Last fall the product was even linked with baseball. "They called themselves the official allergy medicine of Major League Baseball," says Goetzl. That's marketing strategy you usually associate with cars, airlines or soft drinks. After Claritin, the leaders were Propecia ($42 million), Meridia ($29 million), Nasonex ($29 million) and Flonase ($25 million).

The difference between this advertising and the usual direct selling to consumers is that the person who sees the ad can't go right out and buy the product. They have to get their doctor to agree to write them a prescription.

Dr. Alan Sheff, an internist in a Maryland suburb of Washington, sees pluses and minuses in this new phenomenon. "Taking the positive side, I think many patients are unaware of newer treatments that are available and effective for conditions," Sheff says. He used heartburn as an example. A patient may see an add for a heartburn drug and instead of continuing to pop antacids they may go to their doctor and find out they have digestive problems. Or take the Valtrex ads for the suppression of herpes. That ad might bring people into the physician's office to get treatment even when they're not having an outbreak.

Sheff also thinks such advertising could break down some fears or hesitancy some patients have about taking their medicine. "If I have to prescribe a medication and they've heard of it because they've seen it associated with pretty pictures on television, it might lower their resistance to taking it," Sheff says.

That's the kind of thing the drug manufacturers want to hear. At Schering-Plough, the makers of Claritin, executives don't talk about their marketing strategies or how effective their ad campaigns have been. "We believe such advertising can play a key role in informing the public about meaningful advances in drug therapies," says Bill O'Donnell, a spokesman for the New Jersey-based company.

There is a downside, doctors say, to the barrage of television ads. "My greatest concern is what this does to health care and pharmaceutical costs," Sheff says. "The advertising has got to be expensive and you better believe the medicines that are advertised are not available by generic. They are among the most expensive medications on the market and so I have great concerns about forcing my patients to pay for all that direct-to-consumer advertising for these expensive medications."

One reason for the boom is the government's clarification of the rules of this advertising. The Food and Drug Administration rules on drug advertising date back to 1969, explains Nancy Ostrove, branch chief in the division of drug marketing, advertising and communications. Those early regulations said if a drug manufacturer wants to tell people what its drug does, it also has to give the possible side effects. Because manufacturers didn't really want to give the downside, they were getting around those regulations by just mentioning the name of the drug or talking about a malady that could be helped without mentioning the name of a drug.

"That was causing a lot of confusion," Ostrove says. "Consumers and patients were going to the doctor asking for things that were totally inappropriate for them."

So in 1997 the FDA updated the regulations. They now say that prescription drug ads have to give the whole story -- the benefits and the possible side effects. For example, an ad for Tamiflu shows a young woman in pajamas in her bedroom, obviously down and out with the flu. She reaches for a glass of orange juice. In a very soothing voice, an announcer says there is more help for her -- Tamiflu. That calm slow voice continues and, after all of the wonderful possibilities for the drug's effectiveness are explained, the announcer says, a bit more quickly, "One in 10 may experience mild nausea or vomiting."

In addition, the ads have to give consumers a way to find out more about the drugs. They should include an 800 number, a Web site and reference to a print ad about the drug, and they must advise people to talk to their doctors.

"For the most part what we're seeing is reasonable since the 1997 regs," Ostrove says. Drug manufacturers are required to send the FDA copies of all their promotional materials for review, she says, and so far they haven't seen any adverse effects from the ads. Ostrove said the biggest risk she sees from this type of advertising is the possibility of "trivializing prescription drugs."

"There's the risk of patients now believing that their doctors aren't necessary to make the decisions about whether to take a drug," Ostrove says. "There's a belief that perhaps it will affect the patient-physician relationship."

Dr. Edward Benz, chairman of medicine at Johns Hopkins University in Baltimore, sees a potential danger in that a little knowledge of these drugs could be dangerous. "An ad is a sound bite and a sight bite that's on for 30, 40, maybe 60 seconds tops," Benz says. "For something as important and complicated as a potent medication, I don't think that's enough time for people to be forming judgments."

Some consumer groups agree. "The only reason behind this advertising is to create demand for product," says Larry D. Sasich, a pharmicist at Health Research Group, a unit of Public Citizen in Washington, D.C. Sasich points to an article in Medical Marketing and Media, an industry trade journal. "That piece said that over the years the purpose of these ads is to drive consumers into doctors' offices to ask for brand-name drugs."

Industry spokespeople say the aim is to educate. "We believe that a well-informed patient is more apt to obtain appropriate and effective treatment," says Schering's Robinson. "That's the reason why we've implemented a patient information program."