Preliminary pharmacokinetic investigations of hydroxylated metabolites after controlled inhalative and oral consumption of hexahydrocannabinol (HHC)
TL;DR
This study proved the presence of these metabolites in biological samples and provided pharmacokinetic insights for the first time, as they are unlikely to be formed in vivo from corresponding Δ9-tetrahydrocannabinol (THC) metabolites.
Abstract
The pharmacokinetics of the semisynthetic cannabinoid hexahydrocannabinol (HHC) and its 11-nor-carboxy- as well as 11-hydroxy-metabolites has already been the subject of research in various recent publications. However, further metabolism studies showed the presence of other, especially (side-chain-)hydroxylated metabolites in urine and serum. This study aimed to investigate the pharmacokinetics of these metabolites after oral (25 mg fruit gum) and inhalative (three puffs from vape) consumption, using serum and urine samples from a previous study. Serum (up to 48 h) and urine (up to five days) samples of six participants (three per consumption group) were collected at different time points and analyzed by LC-QqTOF and LC-QqLIT. Three metabolites (M1: side-chain-hydroxylated; M2: hydroxylated on alicyclic moiety; M3: 8-OH-HHC) were further investigated. The peak area ratios of analytes and internal standards were plotted against the time after consumption to obtain pharmacokinetic information. Overall, this study proved the presence of these metabolites in biological samples and provided pharmacokinetic insights for the first time. Differences between serum and urine, oral and inhalative consumption as well as inter-individual differences were observed. The investigated metabolites could partially serve as unambiguous consumption markers for HHC, as they are unlikely to be formed in vivo from corresponding Δ9-tetrahydrocannabinol (THC) metabolites.