The online ad is from the U.K., the dollar figure is U.S., and the herb being hawked comes straight from the highlands of northeastern Mexico.

For hundreds of years, salvia divinorum, also known as diviner's sage and magic mint, has been part of the culture of the ancient peoples of the Sierra Mazateca. In a manner similar to peyote, it has been used by local indigenous peoples to induce an altered state for spiritual or meditative purposes.

Unlike peyote, this member of the sage family is legal everywhere but in Australia. That, coupled with Internet hype, has created buzz about salvia— one that rarely survives one experience.

"People who are interested in using drugs for escapist purposes are defeated if they attempt to use salvia in that way," says Daniel Siebert, an ethnobotanist in California who has researched and written widely on the herb, which he also sells online. "It puts you in a very introspective state."

In fact, Siebert says, "Most people don't seem to really like the effects." The vast majority of the thrill-seekers (and even the folks who take this very seriously), rarely purchase the substance again.

"I'd say about 8 per cent re- order."

But first-time users are another story. Elke Hinson, a clerk at a store in Toronto's Kensington Market, Roach-O-Rama, that specializes in all manner of herb-smoking paraphernalia, says he gets inquiries about salvia two or three times a week.

For $120, the store sells two grams of "10X" — a concentrated form of the leaves that claims to be 10 times more powerful than the plant is in its natural state. Two grams of "10X" goes for $40. The experience it can produce is not subtle.

"The first time I tried it, I was almost completely incapacitated — my legs dropped out from under me," says one Roach-O-Rama customer. "Mind you, I was really drunk at the time. So that might have been part of it."

He didn't do his homework. People are advised not to mix salvia with other drugs.

Most of the Web sites — and many of the people who sell it in stores — offer tips on how to use (and warnings on how not to use) salvia divinorum. One of the first rules is: Don't go messing with this stuff if you're out to get loaded.

"It's not a social drug," says Hinson. "If it's your first time, don't do crazy amounts. And have someone there who's like a sober, designated-driver type person."

This concept of a "sober sitter," a trusted friend who will remain clean of all substances and watch over the person doing the salvia, arises on Web site after Web site. That's because, with some people, smoking or ingesting this herb can trigger involuntary movements, even a sleepwalking effect.

People have been known to stumble around blindly, knock things over, even walk into walls. The effects of salvia can hit so swiftly that people drop whatever they're holding — including lighters and pipes. (It's advised that those who wish to try it do so indoors, in relative silence. Do not, it's often warned, try this outside or at a public gathering.)

Online accounts of salvia trips range from magical and mystical to downright frightening. While there are users who describe reflective and philosophical "vision quests" complete with seeing playful spirits, there are others who've spent their time lying on the floor staring at the pattern of carpet fibres. (Some even say they've briefly become the carpet.)

One of the more common sensations, especially at higher doses, seems to be a feeling of disconnect with the body. The phenomenon can range from feeling like you're dreaming and floating, right through to the horrifying perception that your physical self has died — and that your disembodied soul is being unwillingly dragged into the next dimension. Some people have come back from their brief travels (five to 20 minutes if smoked; longer if ingested) absolutely terrified.

As part of his research, Siebert has travelled to the highlands of Mexico. There, he's spoken to shamanic healers and watched them use salvia for spiritual and meditational purposes. "They spend their time chanting and praying devoutly. They use it to make contact with the beings that they're praying to."

That's one of the reasons Siebert is concerned about media coverage and Web site promotions that describe salvia as "legal pot" or compare it with cocaine or LSD. Such inaccurate comparisons tend to attract people with the wrong motivations and expectations, he says.

The active ingredient in this sage, Salvinorin A, has an effect on some of the same brain receptors that opiates hook up with. It does not, however, have the same impact as heroin or morphine — and does not appear to repress breathing.

According to the limited available medical literature, there are no reports of fatal overdoses and the herb does not appear to be addictive. The Centre for Addiction and Mental Health (CAMH), has yet to see someone using this material at a level where it's interfering with their lives.

Dr. David Marsh, the centre's clinical director for addiction medicine, says the vast majority of people who use hallucinogenic drugs try them a few times and stop. That does not mean using salvia is free of adverse consequences. There are risks, he says, such as potentially harming oneself while under the influence. "And anyone who is going to use a psychoactive drug should investigate those risks and make a decision about whether to use that or not from a decision of knowledge."

But is salvia "good"? Is it "bad"? "As a society, we tend to make value judgments about specific substances," Marsh says. "And those judgments affect availability. I don't think, in the end, it's useful to make value judgments. It's more useful to focus on the consequences of use."

So far, the impact of salvia use in Canada, at least on a national scale, has been minimal.

"I don't believe it's a widespread phenomenon," says Sergeant. Jocelyn Mimeault from the national RCMP headquarters in Ottawa. "Last year, the Sûreté du Québec came across three cases involving this product, involving some minors who had experimented with it."

Health Canada says it's monitoring the situation and also says it's aware that salvia does have some traditional uses.

"Should the department compile sufficient evidence that suggests Canadians are abusing the substance and that there's a health risk to Canadians, the department would take appropriate action," says spokesperson Ryan Baker.

In the U.S., the Drug Enforcement Agency has placed salvia on a list of drugs or chemicals "of concern," a status that has no legal implications. "One of the things that we're telling people about salvia is, just because something isn't illegal doesn't mean it's safe," says Tara DeGarmo, a DEA spokesperson in Virginia.

Nor, advocates say, is there any evidence the substance is unsafe. They fear a crackdown might not only deny the minority who seek this particular experience, but could also impair fledgling medical research. Researchers at the University of Mississippi are investigating whether Salvinorin-A could have applications in pain management.

"There are a lot of people doing serious investigations into the compound and derivatives of the compound to look for medically useful drugs," Siebert says.

What's more, advocates argue, informed adults should be entitled to make their own decisions. "We approach this from more of a philosophical standpoint," says Brian Del Re, president of what he calls a "mom-and-pop" online operation that sells salvia from Florida.

"We believe it's not a crime, providing you do it yourself under your own will. There's no victim if there's no crime," he says. Then he adds: "Use it with respect."