They're coated with sugar. In large doses they can produce hallucinations. They're readily available over the counter here in the United States and they just may be the latest craze among teens looking for a cheap and legal high. Cough suppressant tablets intended to bring relief and a full-night's sleep to people suffering from colds can and are being abused, but experts are unsure at this point how much time, attention and effort they should devote to fighting the trend.

Kids know them by a bunch of different names, including "skittles," "dex," and "triple Cs." That last one is a reference the brand name of one of the more popular over-the-counter cold medicines, Coricidin Cough and Cold. The tablets are designed to inhibit the coughing reflex, relieving some of the more annoying symptoms of the common cold. The active ingredient is dextromethorphan (DXM). But in large doses, the chemical can cause a rapid heartbeat, numbness and impaired physical co-ordination, as well as hallucinations and surrealistic emotions.

"I think the abuse of any products that can be dangerous, like dextromethorphan, is a problem," says Tom Hedrick, director of the non-profit Partnership for a Drug-Free America. "The real question that no one has an answer to at the moment is, 'Is it a growing problem, particularly among kids?'"

Mr. Hedrick says DXM abuse is nothing new. It's been around since the 1970s. But now, there are some indications that the number of teenagers overdosing on cough suppressants is on the rise. The American Association of Poison Control Centers has compiled statistics about DXM abuse among teenagers. It reports the number of incidents has doubled over the last three years, from slightly more than 1600 in 2000 to nearly 3300 in 2003. Tom Hedrick says one thing seems to be fueling the increase.

"We found through our research that the only arena in teen culture that was really promoting this was the Internet," he notes. "There was certainly nothing in music videos or fashion or in the arts or in movies, but there were some real tough and strange Internet sites."

Because the promotion of DXM abuse is fairly limited in scope at this point, experts like Tom Hedrick are a little reluctant to address the problem openly. They fear they'll end up giving another drug abuse option to teenagers who don't know that cough suppressants can make you high.

"I think you work kind of through the back door," he explains. "I think you try to reach parents through PTAs and through organizations that are almost totally viewed by, read by, participated in by parents and adults. But you avoid talking about it in a general way in media that may be viewed by kids, not unlike the restrictions they're trying to place on tobacco advertising and alcohol advertising."

So far, three states (New York, New Jersey and California) have proposed measures that would outlaw the sale of cold medicine to anyone under the age of 18. Perhaps not surprisingly, the legislation is opposed by the Consumer Health Care Products Association, the trade group representing the over-the-counter drug industry. President Linda Suydam says her organization has been working with the Partnership for a Drug-Free America to inform parents about DXM abuse, so that lawmakers won't feel the need to pass laws restricting the sale of cough-suppressants.

"Honest consumers suffer when legitimate products are no longer conveniently accessible," she says. "And it's not clear when you're subjecting a retail establishment or even a sales clerk to penalties for the sale of these products that it'll actually prevent children's access to these drugs."

For now, at least, there does seem to be a somewhat "natural" check against the abuse of over-the-counter cough suppressants. While the medicine is available in a tablet form, it's most common incarnation is as a syrup, a rather foul-tasting syrup. And according to Tom Hedrick of the Partnership for a Drug-Free America, the quantity of syrup that's needed to produce a DXM high is so large, that potential abusers usually vomit the stuff up before any real damage can be done.