|CompTox Dashboard (EPA)|
|Chemical and physical data|
|Molar mass||330.468 g·mol−1|
|3D model (JSmol)|
|(what is this?)|
11-Hydroxy-Δ9-tetrahydrocannabinol (11-OH-Δ9-THC, alternatively numbered as 7-OH-Δ1-THC), usually referred to as 11-hydroxy-THC is the main active metabolite of tetrahydrocannabinol (THC), which is formed in the body after Δ9-THC is consumed.
After cannabis consumption, THC is metabolized inside the body by cytochrome P450 enzymes such as CYP2C9 and CYP3A4 into 11-hydroxy-THC and then further metabolized by the dehydrogenase and CYP2C9 enzyme to form 11-nor-9-carboxy-THC (THC-COOH) which is inactive at the CB1 receptors; and further glucuronidated to form 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid glucuronide (Δ9-THC-COOH-glu) where it is excreted in both feces and urine. Both compounds, along with THC, can be assayed in drug tests.
11-hydroxy-THC can be formed after consumption of THC from inhalation (vaping, smoking) and oral (by mouth, edible, sublingual) use, although levels of 11-hydroxy-THC are typically higher when eaten compared to inhalation.
Like Δ9-THC, 11-hydroxy-THC is a partial agonist at the cannabinoid receptor CB1 with significantly higher binding affinity (Ki = 0.37 nM compared to Δ9-THC Ki = 35 nM). With respect to cAMP inhibition at CB1 it displays a similar efficacy to that of Δ9-THC (EC50 = 11 nM vs. EC50 = 5.2 nM, respectively), but a lower maximum response (Emax = 28% vs. Emax = 70%).
In an analysis by the University of Rhode Island on cannabinoids it was found that 11-OH-Δ9-THC had the 3rd highest 3C-like protease inhibitor activity against COVID-19 out of all the cannabinoids tested within that study but not as high as the antiviral drug GC376 (56% 11-OH-Δ9-THC) vs 100% GC376).