WASHINGTON,DC. 27 May, 2015 — Science has spoken! For the first time, a research study of marijuana vs alcohol tells us what we already knew: drinking while you smoke weed increases the THC content in your blood.
According to a study published today in Clinical Chemistry, the journal of the American Association for Clinical Chemistry (AACC), blood concentrations of Δ9-tetrahydrocannabinol (THC), cannabis’s main psychoactive constituent, as well as 11-hydroxy-THC (11-OH-THC), THC’s primary active metabolite, were higher when alcohol was used with cannabis than when study participants used cannabis only.
Lead study author Dr. Marilyn A. Huestis of the National Institute on Drug Abuse, Baltimore, said the high blood-THC levels could “possibly explain increased performance impairment observed from cannabis-alcohol combinations.” Huestis stated, “Our results will help facilitate forensic interpretation and inform the debate on drugged driving legislation.”
Cannabis plus alcohol is among the most frequently detected drug combinations in car accidents, yet because of inadequate research, little is known about the interaction of the two compounds. Combining cannabis and alcohol raises the chance of crashing more than either substance by itself, however using cannabis alone has the lowest risk associated with it. A recent U.S. Department of Transportation study of 1,882 motor vehicle deaths, found an increased accident risk of 7.4 for alcohol use and 8.4 for cannabis and alcohol combined, compared with only 0.7 for cannabis use alone.
Currently, 23 states and the District of Columbia have legalized medical cannabis, and Colorado, Washington, Oregon, and Alaska have decriminalized recreational cannabis use. As cannabis becomes more widely accessible, data will enable more comprehensive assessment of car accident risks.