Effect of fasting and feeding on the pharmacokinetics of a single oral dose of cannabidiol in dogs

Abstract

Cannabinoid research has gained attention in Human and Veterinary Medicine in recent years. Cannabidiol (CBD) is one of the major non-psychotropic cannabinoids found in Cannabis sativa L. CBD has shown a wide variety of pharmacological effects and a safety profile that make it suitable for treating many conditions in dogs. However, the pharmacokinetic (PK) behavior of CBD has not been fully elucidated. CBD is poorly absorbed after oral administration in dogs. Therefore new strategies are needed to increase CBD bioavailability. The main goal of this work was to assess the effect of fasting and feeding on oral PK of CBD in dogs. Five healthy mixed-breed dogs (weight 20 ± 1.4 kg) were used in a controlled cross-over study. All dogs were fasted for 18 hours before given orally 10 mg/kg of CBD (Kanbis®, Elea, Argentina). The Fed group received CBD concomitantly with commercial dry dog food, while the Fasted group received the same food six hours after receiving the CBD dose. After a wash out period of three weeks, animals´ treatments were reversed. Blood samples were taken previous CBD administration and 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, 24, 28 and 36 hours after the treatment. CBD plasmatic concentrations were measured using a RP-HPLC method. Pharmacokinetic parameters were estimated using PK solution® software 2.0.2 (Summit Research Services, USA). A statistically significant difference (p<0.01) was found in Cmax, AUC0-∞ and AUMC, resulting in an average increase of about 530, 680 and 580% respectively in the Fed group. Taking this into consideration, CBD should be given with food in order to maximize its oral bioavailability for treating dogs with systemic diseases. On the contrary, fasting could be useful for concentrating CBD in gastrointestinal tract for local affections.