Washington (CNN) -- The U.S. government moved on Friday to essentially prohibit the sale or distribution of three synthetic forms of marijuana, also known as "fake pot."
The Drug Enforcement Administration (DEA) issued a legal notice classifying the substances as Schedule 1 drugs. It said they are popular on the street and represent a serious public health issue.
The Justice Department, working with federal health officials, has determined the substances, with street names like Spice and K2, have resulted in many visits to emergency rooms or calls to poison control centers.
The most common reactions are vomiting, anxiety, hallucinations, seizures, high blood pressure, or loss of consciousness, the DEA said.
Officials say nearly all the synthetic marijuana mixtures are imported from Asia — mostly China and India.
Five other forms of "fake pot" were banned two years ago, authorities said.
The posting of the notice on Friday means the prohibition can take effect within 30 days.