Can a drug test differentiate between Marinol and the real thing?

Question

Hi Dr...i was wondering if a patient has a prescription for marinol and also uses marijuana, will/can a drug test be able to tell that you've actually smoked marijuana even tho you're using marinol? This is important to be because of work-related. They really can't say anything about the marinol, but just wondering/hoping that a test can't and they they would both show up as marijuana....which would be great for me since they know i'm using marinol...thanks, dr

Answer

Marinol contains delta 9 THC, the main active ingredient in marijuana. Marijuana usually also contains a bunch of closely related compounds, or cannabinoids. Therefore, in theory, if you take marinol you will have only one cannabinoid in your blood, and if you smoke pot, you will have a variety of closely related compounds. (That's why the effects of different batches are so different)

As far as I know, most standard drug screens and tests do not discriminate different cannabinoids, and could not discriminate between marinol and other forms of marijuana. However, I would check with a toxicologist or your doctor to find out more. Obviously, if it mattered enough, such as in a police investigation, they probably could use precise enough methods.

ATP

Andrew T. Pavia, M.D.