Simple Summary
The use of cannabidiol (CBD)-rich hemp-based nutraceuticals is increasing in dogs and cats for disorders related to anxiety, seizures, cancer and pain. To date, there is little information related to appropriate dosing or long-term effects on serum chemistry or complete blood counts (CBC), and little data on the pharmacokinetics of single- or long-term dosing in dogs and cats. Single-dose pharmacokinetics and preliminary 12-week serum chemistry and complete blood counts are reported here showing short pharmacokinetic half-lives of cannabidiol in dogs and cats, with cats showing far lower oral absorption kinetics or rapid elimination suggesting dosing may differ between the two species. Fortunately, there were no changes in physical examination and few changes in the CBC and serum chemistry parameters suggesting the relative safety of oral supplementation over 12 weeks. One of the eight cats displayed a persistent rise in the serum alanine amino transferase (ALT) enzyme outside of the reference range and cats commonly displayed excessive licking and head shaking with administration of the oil. Based on these and other recent data, CBD-rich hemp nutraceuticals appear to be safe in healthy adult dogs, while more work in cats is needed to fully understand utility and absorption.
Abstract
The use of CBD-rich hemp products is becoming popular among pet owners with no long-term safety data related to consumption in adult dogs and cats. The purpose of this study was to determine the single-dose oral pharmacokinetics of CBD, and to provide a preliminary assessment of safety and adverse effects during 12-week administration using a hemp-based product in healthy dogs and cats. Eight of each species were provided a 2 mg/kg total CBD concentration orally twice daily for 12 weeks with screening of single-dose pharmacokinetics in six of each species. Pharmacokinetics revealed a mean maximum concentration (Cmax) of 301 ng/mL and 43 ng/mL, area under the curve (AUC) of 1297 ng-h/mL and 164 ng-h/mL, and time to maximal concentration (Tmax) of 1.4 h and 2 h, for dogs and cats, respectively. Serum chemistry and CBC results showed no clinically significant alterations, however one cat showed a persistent rise in alanine aminotransferase (ALT) above the reference range for the duration of the trial. In healthy dogs and cats, an oral CBD-rich hemp supplement administered every 12 h was not detrimental based on CBC or biochemistry values. Cats do appear to absorb or eliminate CBD differently than dogs, showing lower serum concentrations and adverse effects of excessive licking and head-shaking during oil administration.
