title: Toxicology of avermectins and milbemycins (macrocylic lactones) and the role of P-glycoprotein in dogs and cats.
abstract: The macrocyclic lactones (MLs) are parasiticides able to kill a wide variety of arthropods and nematodes. They have a high margin of safety for labeled indications, and ivermectin has become the best-selling antiparasitic in the world. Dogs of certain breeds and mixtures of those breeds have a defect in the ABCB1 gene (formerly MDR1 gene) that results in a lack of functional P-glycoprotein, which leads to accumulation of the MLs in the central nervous system and a higher risk of adverse effects when exposed. There is no specific antidote for ML toxicosis so the most important part of treatment is good supportive care.
authors.affiliation: ASPCA Animal Poison Control Center, 1717 South Philo Road, Suite 36, Urbana, IL 61802, USA. valentina.merola@aspca.org
authors.forename: Valentina M
authors.initials: VM
authors.lastname: Merola
authors.forename: Paul A
authors.initials: PA
authors.lastname: Eubig
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics* / Q000502:physiology; D000818:Animals; D000871:Anthelmintics / Q000506:poisoning*; D001947:Breeding; D002371:Cat Diseases / Q000139:chemically induced* / Q000235:genetics; D002415:Cats; D004283:Dog Diseases / Q000139:chemically induced* / Q000235:genetics; D004285:Dogs; D007559:Ivermectin / Q000031:analogs & derivatives / Q000506:poisoning; D007783:Lactones; D018942:Macrolides / Q000506:poisoning; D020258:Neurotoxicity Syndromes / Q000209:etiology / Q000235:genetics / Q000662:veterinary*
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000871:Anthelmintics; D007783:Lactones; D018942:Macrolides; D007559:Ivermectin; C019264:avermectin; C027837:moxidectin