The Effects of Acute Δ
Cannabis and its main psychoactive component, Δ We used proton magnetic resonance spectroscopy to measure glutamate levels in the striatum in 20 healthy participants after THC (15 mg, oral) and matched placebo administration in a randomized, double-blind, placebo-controlled design. Psychotic symptoms were measured using the Psychotomimetic States Inventory. We found that THC administration did not significantly change glutamate (glutamate plus glutamine relative to creatine) concentration in the striatum (p .58 scaled Jeffreys-Zellner-Siow Bayes factor 4.29). THC increased psychotic symptoms, but the severity of these symptoms was not correlated with striatal glutamate levels. These findings suggest that oral administration of 15 mg of THC does not result in altered striatal glutamate levels. Further work is needed to clarify the effects of THC on striatal glutamate.