Electroretinographic changes after intravenous lipid emulsion therapy in a dog and a foal with ivermectin toxicosis

Abstract

This case report describes ivermectin-induced blindness in a dog and a foal with normal ophthalmic fundic examinations and attenuated electroretinography (ERG). Subsequent recovery in ERG was noted following intravenous lipid emulsion (ILE) therapy. A dog and a foal were evaluated for ivermectin-induced blindness. Clinical signs included dull mentation, absent pupillary light reflexes (PLRs), and absent menace on presentation. The animals had normal fundoscopic examinations; however, in both cases ERG was consistent with neurosensory retinal dysfunction. Following ILE therapy for ivermectin toxicosis, return of menace, PLRs, and normal mentation were noted, as was improvement in ERG and serum ivermectin levels. These are the first documented cases of ivermectin-induced blindness in a dog and a foal with normal fundic examinations and attenuated ERG. ERG improved in both animals after ILE therapy. ERG may assist in the diagnosis of ivermectin toxicosis in dogs and horses. ILE therapy may hasten recovery in treatment of ivermectin-induced blindness.

The use of intralipid emulsion therapy to treat status epilepticus in a guinea pig (Cavia porcellus) secondary to severe ivermectin toxicity

“…Ivermectin, an avermectin, is a type of macrocyclic lactone that is regularly used in veterinary medicine as a broad spectrum antiparasiticide. 3,5 Ivermectin's mechanism of action is multifactorial and involves both the release of an inhibitory neurotransmitter, gamma amino butyric acid (GABA), in the peripheral nervous system and binding to glutamate-gated chloride ion channels of parasitic invertebrates, ultimately causing neuronal dysfunction, paralysis, and death. 3,[6][7][8][9] Ivermectin is approved by the Food and Drug Administration (FDA) for heartworm prevention and treatment in both dogs and cats, and is an approved anthelminthic in a variety of species, including horses, ruminants, and swine.…”

“…[22][23][24] These reports describe ILE therapy used for several toxicities, including lamotrigine-induced cardiotoxicity, feline permethrin toxicosis, ivermectin toxicity, moxidectin, amlodipine, baclofen, and carbamate. [5][6][7]14,[22][23][24][25][26][27] ILEs are lipid suspensions made up of water and oil and consists of triglyceride-containing oils. 17 It is formulated from soybean oil or a combination of both soybean and safflower oil.…”

“…7,28 Adverse effects mentioned in several reports include lipemia; therefore, serum should be monitored frequently for evidence of lipemia and if seen, no further ILE should be administered. 5,17 Interference with other medications and hypersensitivity reactions has also been documented. 15,29 A case series describes a dog that developed pain and swelling at the administration site secondary to extravasation of the ILE.…”

“…Ivermectin, an avermectin, is a type of macrocyclic lactone that is regularly used in veterinary medicine as a broad spectrum antiparasiticide 3,5 . Ivermectin's mechanism of action is multifactorial and involves both the release of an inhibitory neurotransmitter, gamma amino butyric acid (GABA), in the peripheral nervous system and binding to glutamate‐gated chloride ion channels of parasitic invertebrates, ultimately causing neuronal dysfunction, paralysis, and death 3,6–9 .…”

Therapeutic plasma exchange to mitigate flunixin meglumine overdose in a cria

“…ILE therapy was used in the current case while TPE was being arranged, and therefore its success alone could not be evaluated. ILE has been described for treatment of a variety of drug toxicities in veterinary patients, 10 including goats 11 and equines, 12–14 and is thought to be most effective for lipid solute toxicants such as local anesthetics and ivermectin. ILE has been previously used for treating nonsteroidal anti‐inflammatory drug toxicities in dogs 15,16 and so was a reasonable treatment option in this case.…”