Sydney, Australia: The elimination of the marijuana metabolite carboxy THC is influenced by the body's reaction to stress or dieting, according to a forthcoming study in the British Journal of Pharmacology.

Investigators at the University of Sydney in Australia reported that rats exposed to the stress hormone ACTH experienced increases in marijuana metabolite levels compared to controls. Rats that were deprived of food also experienced spikes in their levels of carboxy THC compared to non-exposed subjects.

Authors of the study said that their findings provide a physiological explanation for why some former users of the drug continue to test positive for it even after long periods of abstinence.

Carboxy THC, the primary inactive marijuana metabolite identified in urine drug screens, accumulates in body fat and similar storage sites. It is released gradually and intermittently over time, with trace levels having been documented in the urine of chronic users for several weeks or even months after past use.

For more information, please contact Paul Armentano, NORML Deputy Director, at: paul@norml.org.