LB-013 - PHARMACOKINETIC EVALUATION OF A NATURAL HEMP EXTRACT-BASED COSMETIC PRODUCT AFTER TOPICAL AND ORAL ADMINISTRATIONS.

M. Jain¹, V. Yellepedi², J. Rower¹, J. Clifford¹, E. Enioutina¹; ¹University of Utah, UT, USA, ²The University of Utah, UT, USA.

Background: Hemp extracts (HE) containing cannabidiol (CBD) are used topically as cosmetic products and may be ingested as a dietary supplement. Some consumers report positive carboxy delta-9-tetrahydrocannabinol (COOH-THC) urinary tests following HE use. The present study investigated the systemic exposure of CBD, THC, and their metabolites following a single dose of oral or topical HE. We also tested whether the urinary samples of participants were THC-positive.

Methods: Twenty healthy adult volunteers (average age 29 years, BMI 18-30) participated in a randomized, open-label, single-dose, crossover study. Participants received 200 mg of HE orally or topically with a 15-day washout between administrations. Plasma samples were collected and analyzed for CBD, THC, and their metabolites using a validated LC-MS/MS method. Several pharmacokinetic (PK) parameters were calculated, including maximum plasma concentration (Cmax) and area under the concentration-time curve (AUC0-24). Urine samples 24 h after doses were tested for COOH-THC using commercial test strips.

Results: All analytes, except for CBD and 7-OH-CBD, were below the limit of quantification (0.5 ng/mL) via LC-MS/MS. PK parameters of CBD and 7-OH-CBD following oral and topical HE administration are shown in Table 1. Compared to topical administration of CBD, Cmax was approximately 31 times higher, and AUC0-24 was 15 times greater (oral vs. topical, 281.0 vs. 19.0 h·ng/mL) following oral absorption. Urine samples were positive for COOH-THC in 35% of participants. It all occurred when an oral dose was administered after the topical dose washout period. The commercial test strips returned a negative test result when tested on analyte-free urine spiked with low or high concentrations of CBD/metabolites.

Conclusion: Oral administration of CBD led to greater systemic exposure. Topical administration shows limited absorption and systemic exposure, likely due to the slower CBD permeation through the skin. The absence of positive reaction to CBD/metabolites in controlled urine tests suggests that participants might have used hemp products between two HE administrations or that concomitant medications used by participants yielded false-positive results.