Interviewer: What is a metabolite?
Brian Sloan: A metabolite is basically a byproduct of a parent drug. In the world of DUI, if someone has done some type of drug like cocaine, PCP, marijuana, or any type of medication, that medication will usually break down to a subset of drugs, which are considered metabolites, or the byproducts of the parent drug. When a drug is taken, it breaks down into metabolites before it is eventually eliminated from one’s system.
Detection of Metabolites
Interviewer: How are metabolites detected, first of all?
Brian Sloan: Well, it can be a metabolite of another drug or it can be a drug itself. For example, with marijuana, marijuana breaks down into the metabolite hydroxy-THC, which then metabolizes into what is called carboxy-THC. THC itself is impairing. Hydroxy-THC itself is impairing. Carboxy-THC is non-impairing.
Interviewer: Is that extracted through a Breathalyzer, through urine, or through blood?
Brian Sloan: It cannot presently be detected by way of a breath test. It’s usually done in a lab through blood or urine to detect the presence of THC or the metabolite carboxy-THC. Labs were not checking in a person’s blood or urine for the presence of hydroxy-THC because hydroxy-THC does not last very long in a person’s system – usually only a couple of hours before it metabolizes into carboxy-THC. With the new ruling that came out from the Arizona Supreme Court, it’s possible that prosecutors are going to talk to the labs and see if they can actually test for the presence of hydroxy-THC to see if there is still an impairing metabolite of marijuana in a person’s system.