Doctors and clinicians at U.S. poison centers say that a synthetic version of marijuana that is frequently sold as incense has spurred symptoms including a fast heart rate, confusion and nausea.
K2, an herbal marijuana substitute also known as "spice," is a blend of herbs sprayed with a synthetic marijuana-like drug, and has spurred at least 112 calls to U.S. poison centers since 2009, including 59 calls since March 1, 2010.
Poison centers in Arkansas, Colorado, Delaware, Georgia, Idaho, Indiana, Iowa, Kentucky, Louisiana, Maryland, Missouri, North Carolina, Texas, Virginia and Wyoming have been among those reporting calls regarding synthetic marijuana.
Among the states that have seen the highest number of calls: Missouri, which Missouri Poison Center Medical Director Anthony Scalzo says has received approximately 40 calls about the substance since last November.
In response to the calls, the state of Missouri issued a health alert about the products, and the St. Charles County Council recently passed an emergency ordinance banning the sale of such products, which are sold in gas stations, convenience stores and "head shops."
Scalzo said the reactions being reported – including agitation, anxiety, an extremely fast, racing heartbeat and elevated blood pressure – are the opposite of what would be expected from marijuana, which is a source of concern.
"This is not what we'd expect from these compounds," he said.
The product is marketed as incense or potpourri and has been sold since 2006 for about $30 to $40 per three-gram bag. Scalzo said parents should be on the lookout for what looks like incense in their child's room and watch to see if their children seem more anxious than usual.
No deaths have been reported, but symptoms have also included agitation, dizziness, nausea, vomiting, tremors and chest pain in some cases.