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Note:
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academies
Joint Event on
S e p t e m b e r 1 0 - 1 1 , 2 0 1 8 | D u b l i n , I r e l a n d
TOXICOLOGY AND PHARMACOLOGY
PHARMACEUTICAL CHEMISTRY & DRUG DISCOVERY
&
Global Congress on
International Conference on
Pharma Chem Congress 2018 & Toxicology Congress 2018
Asian Journal of Biomedical and Pharmaceutical Sciences
|
Volume 8
Asian J Biomed Pharmaceut Sci 2018, Volume 8 | DOI: 10.4066/2249-622X-C2-006
RELATIONSHIP BETWEEN ON-SITE ORAL FLUID TESTING AND THC
PLASMA CONCENTRATIONS IN MARIJUANA SMOKERS
Simon N and Alvarez J C
Aix-Marseille University, France
T
he study aimwas to define the pharmacokinetic of delta-9-tetrahydrocannabinol (THC) and 11- OH-THC following two inhaled
doses of cannabis and to evaluate the relationship between THC plasma concentrations and on-site oral fluid screening de-
vice Drugwipe 5S
®
in chronic and occasional marijuana smokers, 30 healthy male volunteers: 15 regular (1-2 joints/day) and 15
occasional (1-2 joints/week) consumers aged 18-34 were included. Blood concentrations of THC were measured after controlled
inhalation of 10 mg or 30 mg. Blood samples were collected 5, 15, 30 minutes, 1, 2, 4, 6, 8, 10, 12 and 24 hours after the end of the
joint, and an oral fluid test was carried out at the same times up to six hours with a final test at 24 h before leaving the study. First,
a population PK analysis was performed using a non-linear mixed effects modelling. Then, the relationship between a positive
oral fluid testing and several covariates was evaluated using a logistic regression analysis. For THC, the best base model used
three-compartments with zero-order input and first-order output. The group had a significant effect on relative bioavailability
(F1). Chronic cannabis users had a 2.41 times greater value of F1 than the occasional users. Dose achieved to non-linearity with
a decrease by 0.68 of F1 for 30 mg compared to 10 mg. For 11-OH-THC, the model was a two-compartments with first-order
input. The logistic model describing the probability of a positive oral fluid testing included the THC plasma concentrations (es-
timate 246, IC95: 169-547) and the group (estimate -1.81, IC95: -3.09- -0.78) with an intercept of -1.20 (-2.36- -0.47). This study
described a non-linear relative bioavailability of THC with higher doses leading to a lower exposure. Further, with a same THC
concentration, users who smoke cannabis occasionally have a higher probability to be screened positive compared to daily users.