They say two teenagers recently ended up in emergency rooms after ingesting substances containing methanone or XRL11.
"It certainly is a threat to underage kids who may get access to it," said Rich Hogan, attorney for the health department.
The state banned a version of fake pot, K2, in 2010. Making permanent the ban on the chemical compound is aimed at getting other varieties of synthetic drugs off the streets, Hogan said.
That may prove to be difficult.
Despite the K2 ban, Little Rock police seized more than 10 pounds of K2 from Smoker's Corner at 1801 Green Mountain Drive and two pounds from Sunshine Food Mart at 3200 Baseline Road. The owners are facing drug charges.
Little Rock Police Sgt. Cassandra Davis said she hopes a permanent ban on methanone will deter people trying to sell synthetic drugs.
As it stands, the ban on methanone is temporary.
The board of health is slated to meet in November to hold a public hearing on a proposed permanent ban.
The health department in January will ask state lawmakers to approve it.