International Journal of Current Microbiology and Applied Sciences
ISSN: 2319-7706 Volume 6 Number 11 (2017) pp. 1452-1455 Journal homepage: http://www.ijcmas.com
Case Study https://doi.org/10.20546/ijcmas.2017.611.173
Ivermectin Toxicity in a German Shepherd Cross Breed Dog: A Case Study
Sheikh Tajamul Islam*, Mohd Younis Ganaie, Syed Shakeebah Kubra,
Rayeesa Ali and Anand Kumar Singh
Department of Veterinary Medicine, International Institute of Veterinary Education and
Research (IIVER), Rohtak Haryana-124001, India *Corresponding author
ABSTRACT
A German Shepherd cross male dog one year old weighing 12 kg was presented to Teaching Veterinary clinics complex, International Institute of Veterinary Keywords Education and Research (IIVER), Rohtak Haryana for treatment. The dog was treated for tick infestation by owner. History revealed that about 1.5 ml of Dogs, Ivermectin, Toxicity, Therapeutic ivermectin (I-mac) was injected intramuscularly. Abnormal clinical signs were management. observed by owner 12 hours after injection. Clinical examination revealed Article Info hypothermia (98.5˚F), ataxia, partial blindness, dilated pupil, negative papillary light reflex, weakness, incoordination and behavioural changes. Therapeutic Accepted: management was done with the administration of atropine sulphate @ 0.02-0.04 12 September 2017 mg/kg BW IV stat, neostigmine @ 0.05mg/kg BW SC repeated 6 hourly and Available Online: 12 November 2017 dexamethasone @ 0.25-0.5mg/kg BW IM BID and optineuron @ 1 ml total dose with infusion of 200 ml dextrose (5%) IV. The dog recovered uneventfully after treatment.
Introduction
Ivermectin is an antiparasitic drug belonging medicine and is approved for use in dogs as a to the avermectin family of compounds. heartworm preventative at a dosage of 6 Ivermectin is a mixture of 80% or more of an μg/kg PO once a month. Off-label use of the analog of avermectin B1a (AB1a) and 20% or drug in dogs for ectoparasites and less of an analog of avermectin B1b. These endoparasites is common, with dosage compounds are 2 of 4 avermectins produced recommendations ranging from 50 to 300 by the actinomycete Streptomyces avermitilis. μg/kg PO or subcutaneously Plumb et al., Although similar in structure to the (1995). macrocyclic lactones, avermectins have no antibacterial or antifungal activity. They do The median lethal dose (LD50) of ivermectin have a broad spectrum of activity against for beagle dogs has been reported to be about nematode and arthropod parasites of both 80 mg/kg, and the highest single oral dose in plants and animals Campbell (1983). beagle dogs without an adverse clinical effect Ivermectin has been widely used in veterinary was 2 mg/kg Campbell (1989). Some Collies
are extremely sensitive to ivermectin, with Treatments and Discussion
notable individual variation. A dose of 50–60 μg/kg ivermectin was found to be safe in Therapeutic protocol for ivermectin toxicity is Collies known to be susceptible to the drug only managemental care, supportive therapy Fassler et al., (1991) and Pulliam et al., and symptomatic treatment as there is no (1985). Ivermectin is widely used endectocide specific antidote for ivermectin toxicity. The in canines and toxicity is seen when excessive dog was treated with the administration of dose is administered in pets that are sensitive atropine sulphate @ 0.02-0.04 mg/kg BW IV to drugs. Toxicity results in any clinical signs stat, neostigmine @ 0.05mg/kg BW SC ranging from mild to severe and death may repeated 6 hourly and dexamethasone @ occur. 0.25-0.5mg/kg BW. IM BID and optineuron @ 1 ml total dose with infusion of 200 ml Some breeds are sensitive to lower doses of dextrose (5%) IV. The dog recovered ivermectin such as Collie, Australian uneventfully after treatment. Shepherd and Shetland Sheepdogs. Occurrence of toxicity in selective breeds Collie breed of dogs are more susceptible to may be due to the reason that these breeds ivermectin and tolerate only up to 0.1 mg/kg have comparatively more permeable blood dose rate of ivermectin Paul et al., (1987).The brain barrier to the drug Houstonet et al., margin of safety for ivermectin in most breeds (1987). of dog is well over 100 times the recommended dose but in Collies it is about History and Clinical observations 16 times the usual dose. Clinical signs of toxicity were reported in two Australian A German shepherd cross male dog one year shepherds receiving ivermectin at oral dosage old weighing 12 kg was presented to of 0.17 mg/kg and 0.34 mg/kg respectively Teaching Veterinary clinics complex, Hadrick et al., (1995). Occurrence of toxicity International Institute of Veterinary Education in selective breeds, may be due to the reason and Research (IIVER), Rohtak Haryana for that these breeds have comparatively more treatment with complaint of depression permeable blood brain barrier to the drug (Figure 1a), ataxia, partial blindness, dilated Houstonet et al., (1987) or due to an pupil (Figure 1b), negative pupillary light autosomal recessive trait (MDR-1) gene that reflex, weakness, incoordination and causes a defect in the p-glycoprotein, which is behavioural changes. The dog was treated for a multidrug transporter in the blood brain tick infestation by owner for tick infestation. barrier and this leads to passage of ivermectin in to the brain at low dosages thus causing The dog was injected 1.5 ml of ivermectin toxicity Kant (2007). In present case, the intramuscularly 24 hours before to treat animal was young and the blood brain barrier ectoparasites. Clinical examination revealed might not have been fully developed leading hypothermia (98.5˚F), mydriasis, tachycardia to toxicity. Side effects of urgent concern are (110 beats per minute), dysponea with dilated pupils and drunken gait which can respiration rate of (17 breaths per minute), progress to respiratory paralysis and death if incoordination, seizures and unable to stand medication is not withdrawn and supportive properly. Hematobiochemical parameters care is not initiated. Unfortunately, ivermectin were found normal (Table 1) and on the basis toxicity cannot be reversed and therefore, it is of anamnesis and clinical observations the wise to treat the symptoms to the best our case was diagnosed as ivermectin toxicity. potential and ability.
Fig.1 Showing mydriasis of eye bilaterally (A) and depression (B) of dog affected with ivermectin toxicity
A B
Physostigmine is an anticholinesterase agent severe lethargy or coma. Improvement in
that results in the accumulation of increased clinical signs occurred within minutes of amounts of acetylcholine (ACh) at the physostigmine administration, but the effect synapse. This increase in ACh increases the only lasted 30–90 minutes. It was not possible conductance of sodium ions into the to determine if physostigmine administration postsynaptic membrane, causing in these animals hastened their recovery depolarization to occur. In an uncontrolled Tranquilli (1987). Increased limb movements trial, Collies dosed with ivermectin were also were reported after physostigmine treated with physostigmine if they showed administration to 1 of 2 Australian Shepherds
suffering from ivermectin toxicity Hopkins et American Veterinary Medical
al., (1990). A Collie with ivermectin toxicity Association, 206 (8): 1147. was treated with physostigmine. The dog was Hopkins, K. D. Marcella, K. L. Strecker, A. in sternal recumbency before therapy and was E. (1990). Ivermectin toxicosisin a dog. able to stand and walk unaided 15 minutes Journal of American Veterinary after treatment. The improvement only lasted Medical Association, 197:93–94. 45 minutes, after which the dog was Houston, D. Parent, J. and K. Matushek. recumbent again Smith et al., (1990). (1987) Ivermectin toxicosis in dogs. Journal of American Veterinary Management of ivermectin intoxication may Medical Association, 191(1):78. be aided by an understanding of the action of Kant, V. (2007) Ivermectin toxicity in Dogs the drug and its interaction with other and Cats. Pashudhan, 33(11). therapeutic agents. After these considerations, Paul, A. Tranquilli, W. and Seward, R. (1987) the prognosis for complete recovery from Clinical observations in collies given ivermectin toxicity is good. ivermectin orally. American Journal of Veterinary Research, 48(4):684. References Plumb, D. C. (1995). Veterinary Drug Handbook, 2nd ed. Ames, IA: Iowa Campbell, W. C. Ivermectin and Abamectin. State University Press. New York, NY: Springer-Verlag. 1989. Pulliam, J. D., Seward, R. L., Henry, R. T., Campbell, W. C., Fisher M. H., and Stapley and Steinberg S. A. (1985). E.O. (1983). Ivermectin: A potent new Investigating ivermectin toxicity in antiparasitic agent. Science, 221:823– Collies. Veterinary Medicine, 80:33–40. 827. Smith, R. A. Stronski, E. J. and Beck, B. E. Fassler, P. E., Tranquilli, W. J., and Paul, A. (1990). Death of a Rough Collie J. (1991) Evaluation of the safety of exposed to an ivermectin-based paste. ivermectin administered in a beef based Canadian Veterinary Journal, 31:221 formulation to ivermectin sensitive (letter to the editor). Collies. Journal of American Veterinary Tranquilli, W. J. Paul, A. J. and Seward, R. L. Medical Association, 199: 457–460. (1987). Response to physostigmine Hadrick, M. Bunch, S. and Kornegay, J. administration in collie dogs exhibiting (1995) Ivermectin toxicosis in two ivermectin toxicosis. Journal of Australian shepherds. Journal of Veterinary Pharmacology, 10:96–100.
How to cite this article:
Sheikh Tajamul Islam, Mohd Younis Ganaie, Syed Shakeebah Kubra, Rayeesa Ali and Anand Kumar Singh. 2017. Ivermectin Toxicity in a German Shepherd Cross Breed Dog: A Case Study. Int.J.Curr.Microbiol.App.Sci. 6(11): 1452-1455. doi: https://doi.org/10.20546/ijcmas.2017.611.173
