On Wednesday, in New Haven, Connecticut, there were at least 76 overdoses in 24 hours from “synthetic” marijuana. The term, “synthetic” marijuana, however, is misleading. Here’s a look at why.

Products labeled as synthetic marijuana are often plant matter sprayed with lab-created drugs. Those drugs, or combination of drugs, are designed to bind to the same receptors in the body as naturally occurring cannabinoids attach to. But because they are different in composition, they often lead to dangerous and unpredictable reactions.