Lab-made pot products boast catchy, harmless-sounding names, but physicians are warning parents and teens that the drugs are causing a growing number of hospitalizations and deaths, NBC’s Today.com reported.

Synthetic cannibinoids—called “spice,” “Scooby snacks” or “K2” on the streets—are said to hit the same receptors on the brain as real marijuana. That’s how they produce a high.

But health experts say these spice products are often far more potent and ultimately more dangerous than illegal, homegrown pot. Fake marijuana has been shown to cause anxiety, hallucinations, agitation, kidney damage, seizures and even abrupt deaths. What’s more, the chemical compounds in these drugs don’t show up on tests, and fake pot products can be easily bought online or at convenience stores or head shops across the country.

“It’s a misnomer to even call it synthetic marijuana,” warned clinical toxicologist Aaron Schneir, MD, PhD, a clinical professor of emergency medicine at the University of California at San Diego. “There has been an explosion of [ER] visits over the past few years, and [the synthetic products] haven’t been around very long.”

In February 2013, the U.S. Drug Enforcement Administration (DEA) started cracking down on spice by registering four new synthetic cannibinoids as Schedule 1 drugs, on par with cocaine, heroin and real marijuana in the eyes of the law. But labs keep inventing new chemical forms of the drugs, making it hard for federal regulators to keep up.

Also, speaking of fake stuff folks light up and puff: There is mounting skepticism in the medical community about the safety of e-cigarettes as an alternative to those made from tobacco. Click here for more information.