DENVER (AP) — Colorado’s tourists aren’t just buying weed now that it’s legal — they’re ending up in emergency rooms at rates far higher than residents.

That’s according to a study that will be published Thursday in the New England Journal of Medicine.

Doctors reviewed marijuana-related emergency-room admissions at a hospital near Denver International Airport during 2014, the first year recreational pot sales became legal.

The physicians found that the rate of emergency-room visits possibly related to marijuana doubled among out-of-state residents.

Among Colorado residents, the rate of emergency-room visits possibly related to cannabis use did not change significantly between 2013 and 2014.

The doctors say there needs to be more education about pot aimed at visitors.