'Spice' Overdoses Send More Than 300 to ER in 2 Weeks

More than 300 people have gone to the emergency room after using synthetic marijuana -- also known as "spice" -- in the past month, health officials in Mississippi and Alabama announced.

Spice, which refers to several brands of synthetic marijuana sold illegally in convenience stores, has prompted 227 emergency room visits in Mississippi since April 2, officials said. And in Alabama, there have been 98 "suspicious" emergency room visits in the past month, leading doctors to believe the patients had used spice, the health department said.

"We want the public to be aware of the toxic effects and other dangers associated with synthetic marijuana use," Alabama state health officer Dr. Donald Williamson said in a news release.

In the short term, symptoms include seizures, hallucinations, increased heart rate, suicidal thoughts, anxiety attacks and uncontrollable rage, he said. The long-term effects are unknown.

Health officials warned that spice contains "unpredictable" chemicals that are not natural and can also result in a coma.

Meanwhile, a 47-year-old Virginia woman died and six others were hospitalized over the same weekend in Hampton, Virginia, according to ABC affiliate WVEC-TV.

New Hampshire officials declared a state of emergency in August after synthetic pot sent 20 people to the hospital in just a few days.

Spice is meant to mimic tetrahydrocannabinol ,or THC, the chemical found in cannabis. Although it's marketed as "natural," it's anything but.

"The distributor buys powder from China, wets it with acetone to make liquid and sprays it over inert plant material," U.S. Drug Enforcement Administration spokeswoman Barbara Carreno said."Then they mix that all up let it dry so the acetone evaporates out. The plant material is coated with chemicals. They take that and put it in those little packets."

The DEA has found it's rarely mixed in a lab. Instead, they've found distributors concocting synthetic pot in animal feed troughs, on tarps in their garages and in storage units, she said.

The packets have several different brand names, including Mr. Smiles, Black Mamba, K2 and Spice, she said. But even within the same brand, the plant materials are often sprayed with different chemicals.

"The one overriding message on these things is that you don't know what you're getting," Carreno said. "There's no consistency in the chemical in it, and there's no consistency in potency of the chemical that's in it."