Drivers that have vaped a combination of THC and CBD or THC alone show signs of “modest” impairment up to four hours later, a study published Tuesday by JAMA found.
The impairment from vaping compounds containing the main ingredients of marijuana is equivalent to that seen in drivers with blood alcohol concentrations of 0.05 percent, or roughly half the legal limit for driving under the influence in most states, the researchers said.
“[Our] study shows that cannabis-induced driving impairment varies with cannabis strains,” said study co-author Dr. Johannes Ramaekers in an interview with United Press International news wire service. “The implication for the general public is that the cannabis-induced driving impairment should be acknowledged as a public health risk while taking into account that impairment may differ between cannabis strains and depends on time after use.”
Compounds containing higher amounts of tetrahydrocannabinol, or THC, “are typically used for intoxication,” while those with cannabidiol, or CBD, which are not intoxicating, are prescribed for the treatment of epilepsy, anxiety, psychosis and neurological disorders, they said.