It looks like marijuana but it's not. Even so, teens and young adults from coast to coast are smoking it and getting high.
"I think it's becoming very popular because, number one, it's legal. And there's an entire trend in our country called legal highs," said Dr. Anthony Scalzo, Toxicologist, Cardinal Glennon Children's Medical Center.
It's a mixture of dried herbs sprayed with one or more chemicals. It's often sold as incense or potpourri under names like K-2, Serenity Now, and Zohai. But it has a worrisome nickname: fake marijuana.
The Drug Enforcement Administration believes the chemicals on these herbs are similar to THC, the active ingredient in marijuana.
"Most of these chemicals are not controlled chemicals right now. They're not under DEA's regulatory authority," said Supervisory Special Agent Gary Boggs, DEA.
Toxicologist Dr. Anthony Scalzo says a growing number of teens, young adults, and even middle-aged men and women are landing in the ER after smoking fake marijuana.
The synthetic substance has spurred at least 112 calls to US poison centers since 2009, including 59 since March 1 of this year.
"They're having racing heart beats up to 140, 150. The highest I can recall is 170 beats per minute. Normal is 70 to 80 beats per minute. And their blood pressures are elevated," said Dr. Scalzo.
There have even been cases of hallucinations and tremors. These reactions are the opposite of what would be expected from marijuana. And that's what has health officials concerned.
"We're trying to find out what is in some of the products that we're dealing with. And it could be a contaminant. I mean, we don't know that for sure, but typically these synthetic chemicals should not be causing this kind of reaction," said Dr. Scalzo.
Most parents have no idea these products are on the market, and many physicians are still unaware of the problem. The American Association of Poison Control Centers has just issued a health alert, and Dr. Scalzo is helping spread the word.
"So there's people out there that are not coming to get medical attention that are having adverse affects. And somewhere along the line this product is going to meet an individual who has, perhaps, a weakness in their blood vessels or their cardiovascular system," he said.
Another worry? Information about the substance is reaching teens at lightning speed. Online forums and YouTube are filled with chatter about fake pot.
"I think it's important that the parents stay involved with their children, that they know what they're doing, both in just real life, as well as what they're doing on the Internet," said Boggs.
The DEA says it isn't clear who is manufacturing these products or where they're coming from.
Dr. Scalzo says be on the lookout for what looks like incense or "oregano" in your child's room. Also, watch to see if your child seems more anxious than normal.
So called "fake marijuana" is widely available and can be found at head shops, bait and tackle shops, even on the Internet.
If you have any questions, call The Poison Control Center at 1-800-222-1222.