Use of Terpenoids to Control Helminths in Small Ruminants

Abstract

Gastrointestinal nematodes affect the animal's health and cause economiclosses in meat, milk, and wool production. Essential oils and their terpenoids have beenshown to effectively control gastrointestinal nematodes and may be an alternative tocontrol gastrointestinal nematodes. The great advantage of terpenoids is the possibilityof acting on the parasite in a multidirectional way on the neuromuscular system andbody structures of nematodes. The current chapter describes the pharmacological basisof the combination of terpenes and synthetic anthelmintics as an alternative forincreasing antiparasitic efficacy. It is necessary to evaluate if these combinations showantagonist, additive or synergic effects at the pharmacokinetic and pharmacodynamiclevels. The physicochemical properties, pharmacokinetic features and potential drugdrug interactions at the metabolism or transport level of monoterpenes may be relevantfor obtaining effective concentrations against different nematodes. In this context, theprediction of absorption, distribution, metabolism and excretion (ADME) is essential tooptimize the anthelmintic action of these compounds. The rapid absorption andelimination of monoterpenes after their oral administration may directly influence thedrug concentration level attained at the target parasites and the resultantpharmacological effect. Therefore, investigations on the dose schedule, administrationroute and type of pharmaceutical formulation are necessary. The integration of in vitroassays, in silico analysis, and in vivo pharmaco-parasitological studies are relevant tocorroborate the kinetic/metabolic interactions and the efficacy of bioactive naturalproducts combined with synthetic anthelmintics.