Cover Journal of the American Veterinary Medical Association
Journal of the American Veterinary Medical Association
ISSN:
0003-1488
Publication Date:
01 Sep 2009
  • 1.

    Mealey KL, Bentjen SA, Gay JM, et al. Ivermectin sensitivity in collies is associated with a deletion mutation of the mdr1 gene. Pharmacogenetics 2001;11:727–733.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 2.

    Hsu WH, Wellborn SG, Schaffer CB. The safety of ivermectin. Compend Contin Educ Pract Vet 1989;11:584–588.

  • 3.

    Roder JD, Stair EL. An overview of ivermectin toxicosis. Vet Hum Toxicol 1998;40:369–370.

  • 4.

    Plummer CE, Kallberg ME, Ollivier FJ, et al. Suspected ivermectin toxicosis in a miniature mule foal causing blindness. Vet Ophthalmol 2006;9:29–32.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 5.

    Godber LM, Derksen FJ, Williams JF, et al. Ivermectin toxicosis in a neonatal foal. Aust Vet J 1995;72:191–192.

  • 6.

    Burrough S. Ivermectin toxicity in horses. N Z Vet J 1986;34:137–138.

  • 7.

    Hautekeete LA, Khan SA, Hales WS. Ivermectin toxicosis in a zebra. Vet Hum Toxicol 1998;40:29–31.

  • 8.

    Pérez R, Godoy C, Palma C, et al. Plasma profiles of ivermectin in horses following oral or intramuscular administration. J Vet Med A Physiol Pathol Clin Med 2003;50:297–302.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 9.

    Campbell WC, Benz GW. Ivermectin: a review of efficacy and safety. J Vet Pharmacol Ther 1984;7:1–16.

  • 10.

    Leaning HD. The efficacy and safety evaluation of ivermectin as a parenteral and oral antiparasitic agent in horses, in Proceedings. 29th Annu Conv Am Assoc Equine Pract 1983;319–328.

    • Search Google Scholar
    • Export Citation
  • 11.

    Pulliam JD, Preston JM. Safety of ivermectin in target animals. In: Campbell WC, ed. Ivermectin and abamectin. New York: Springer-Verlag Inc, 1989;149–161.

    • Search Google Scholar
    • Export Citation
  • 12.

    Pérez R, Cabezas I, Sutra JF, et al. Faecal excretion profile of moxidectin and ivermectin after oral administration in horses. Vet J 2001;161:85–92.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 13.

    Gokbulut C, Nolan AM, McKellar QA. Plasma pharmocokinetics and faecal excretion of ivermectin, doramectin and moxidectin following oral administration in horses. Equine Vet J 2001;33:494–498.

    • Search Google Scholar
    • Export Citation
  • 14.

    Pérez R, Cabezas I, Garcia M, et al. Comparison of the pharmacokinetics of moxidectin (Equest) and ivermectin (Eqvalan) in horses. J Vet Pharmacol Ther 1999;22:174–180.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 15.

    Houston DM, Parent J, Matushek KJ. Ivermectin toxicosis in a dog. J Am Vet Med Assoc 1987;191:78–80.

  • 16.

    Hopkins KD, Marcella KL, Strecker AE. Ivermectin toxicosis in a dog. J Am Vet Med Assoc 1990;197:93–94.

  • 17.

    Hadrick MK, Bunch SE, Kornegay JN. Ivermectin toxicosis in two Australian shepherds. J Am Vet Med Assoc 1995;206:1147–1152, discussion 1150–1152.

    • Search Google Scholar
    • Export Citation
  • 18.

    Hopper K, Aldrich J, Haskins SC. Ivermectin toxicity in 17 collies. J Vet Intern Med 2002;16:89–94.

  • 19.

    Paul AJ, Tranquilli WJ, Seward RL, et al. Clinical observations in Collies given ivermectin orally. Am J Vet Res 1987;48:684–685.

  • 20.

    Beal MW, Poppenga RH, Birdsall WJ, et al. Respiratory failure attributable to moxidectin intoxication in a dog. J Am Vet Med Assoc 1999;215:1813–1817.

    • Search Google Scholar
    • Export Citation
  • 21.

    Snowden NJ, Helyar CV, Platt SR, et al. Clinical presentation and management of moxidectin toxicity in two dogs. J Small Anim Pract 2006;47:620–624.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 22.

    Lewis DT, Merchant SR, Neer TM. Ivermectin toxicosis in a kitten. J Am Vet Med Assoc 1994;205:584–586.

  • 23.

    Muhammad G, Abdul J, Khan MZ, et al. Use of neostigmine in massive ivermectin toxicity in cats. Vet Hum Toxicol 2004;46:28–29.

  • 24.

    Button C, Barton R, Honey P, et al. Avermectin toxicity in calves and an evaluation of picrotoxin as an antidote. Aust Vet J 1988;65:157–158.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 25.

    Seaman JT, Eagleson JS, Carrigan MJ, et al. Avermectin B1 toxicity in a herd of Murray Grey cattle. Aust Vet J 1987;64:284–285.

  • 26.

    Johnson PJ, Mrad DR, Schwartz AJ, et al. Presumed moxidectin toxicosis in three foals. J Am Vet Med Assoc 1999;214:678–680.

  • 27.

    Müller JM, Feige K, Kästner SB, et al. The use of sarmazenil in the treatment of a moxidectin intoxication in a foal. J Vet Intern Med 2005;19:348–349.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 28.

    Khan SA, Kuster DA, Hansen SR. A review of moxidectin overdose cases in equines from 1998 through 2000. Vet Hum Toxicol 2002;44:232–235.

    • Search Google Scholar
    • Export Citation
  • 29.

    Pulliam JD, Seward RL, Henry RT, et al. Investigating ivermectin toxicity in Collies. Vet Med (Praha) 1985;80:33–40.

  • 30.

    Garland T, Bailey EM, Reagor JC, et al. Probable interaction between solanum eleagnifolium and ivermectin in horses. In: Garland T, Barr AC, eds. Toxic plants and other natural toxicants. Wallingford, England: CAB International, 1998;423–427.

    • Search Google Scholar
    • Export Citation
  • 31.

    Mendell C. Four horses dead, one ill; dewormer questioned. The Horse 2006;May:24.

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Ivermectin toxicosis in three adult horses

Tamara M. SworDepartment of Large Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843.

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Jamie L. WhittenburgDepartment of Large Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843.

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M. Keith ChaffinDepartment of Large Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843.

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DOI:
https://doi.org/10.2460/javma.235.5.558
Volume/Issue:
Volume 235: Issue 5
Online Publication Date:
01 Sep 2009
Restricted access
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Abstract

Case Description—3 adult Quarter Horses were evaluated for acute, progressive neurologic signs 18 hours after oral administration of 1 dose of 1.87% ivermectin paste.

Clinical Findings—Clinical signs included depression, forelimb and hind limb ataxia, drooping of the superior and inferior lips, and muscle fasciculations. Bilateral mydriasis, decreased pupillary light reflexes, and absent menace reflexes were evident. Clinical signs progressed in severity for 36 hours after administration of the ivermectin.

Treatment and Outcome—All horses were treated supportively with IV administration of fluids and anti-inflammatory medications. Two horses survived with no apparent long-term sequelae. One horse was euthanized, and a high concentration of ivermectin was detected in its brain tissue at postmortem examination. Analysis of the ivermectin concentration in the paste product revealed that the concentration was approximately that indicated on the packaging.

Clinical Relevance—Ivermectin toxicosis is an uncommonly reported condition in equids that should be considered when acute neurologic impairment develops after ivermectin administration. Recovery is possible with supportive care and time.

Abstract

Case Description—3 adult Quarter Horses were evaluated for acute, progressive neurologic signs 18 hours after oral administration of 1 dose of 1.87% ivermectin paste.

Clinical Findings—Clinical signs included depression, forelimb and hind limb ataxia, drooping of the superior and inferior lips, and muscle fasciculations. Bilateral mydriasis, decreased pupillary light reflexes, and absent menace reflexes were evident. Clinical signs progressed in severity for 36 hours after administration of the ivermectin.

Treatment and Outcome—All horses were treated supportively with IV administration of fluids and anti-inflammatory medications. Two horses survived with no apparent long-term sequelae. One horse was euthanized, and a high concentration of ivermectin was detected in its brain tissue at postmortem examination. Analysis of the ivermectin concentration in the paste product revealed that the concentration was approximately that indicated on the packaging.

Clinical Relevance—Ivermectin toxicosis is an uncommonly reported condition in equids that should be considered when acute neurologic impairment develops after ivermectin administration. Recovery is possible with supportive care and time.

Contributor Notes

Dr. Whittenburg's present address is Animal Medical Center, 5204 80th St, Lubbock, TX 79424.

The authors thank Dr. John Reagor for his assistance with ivermectin assays and toxicologic analyses.

Address correspondence to Dr. Swor.