• 1. Henkin RI. Drug-induced taste and smell disorders: incidence, mechanisms and management related primarily to treatment of sensory receptor dysfunction. Drug Saf 1994; 11: 318377.

    • Search Google Scholar
    • Export Citation
  • 2. Kharoubi S. Olfaction disorders: preliminary findings and results in 45 cases. J Laryngol Otol 2001; 122: 4349.

  • 3. Henkin RI, Levy LM, Fordyce A. Taste and smell function in chronic disease: a review of clinical and biochemical evaluations of taste and smell dysfunction in over 5000 patients at The Taste and Smell Clinic in Washington, DC. Am J Otolaryngol 2013; 34: 477489.

    • Search Google Scholar
    • Export Citation
  • 4. Fonteyn S, Huart C, Deggouj N, et al. Non-sinonasal-related olfactory dysfunction: a cohort of 496 patients. Eur Ann Otorhinolaryngol Head Neck Dis 2014; 131: 8791.

    • Search Google Scholar
    • Export Citation
  • 5. Myers LJ, Hanrahan LA, Swango LJ, et al. Anosmia associated with canine distemper. Am J Vet Res 1988; 49: 12951297.

  • 6. Myers LJ, Nusbaum KE, Swango LJ, et al. Dysfunction of sense of smell caused by canine parainfluenza virus infection in dogs. Am J Vet Res 1988; 49: 188190.

    • Search Google Scholar
    • Export Citation
  • 7. Ezeh PI, Myers LJ, Hanrahan LA, et al. Effects of steroids on the olfactory function of the dog. Physiol Behav 1992; 51: 11831187.

    • Search Google Scholar
    • Export Citation
  • 8. Altom EK, Davenport GM, Myers LJ, et al. Effect of dietary fat source and exercise on odorant-detecting ability of canine athletes. Res Vet Sci 2003; 75: 149155.

    • Search Google Scholar
    • Export Citation
  • 9. Myers LJ. Dysosmia of the dog in clinical veterinary medicine. Prog Vet Neurol 1990; 1: 171179.

  • 10. Hirano Y, Oosawa T, Tonosaki K. Electroencephalographic olfactometry (EEGO) analysis of odor responses in dogs. Res Vet Sci 2000; 69: 263265.

    • Search Google Scholar
    • Export Citation
  • 11. Fjellaner R, Andersen EK, McLean IG. A training program for filter-search mine detection dogs. Int J Comp Psychol 2002; 15: 278287.

    • Search Google Scholar
    • Export Citation
  • 12. Author or authoring group. Training of mine detection dogs in Bosnia and Herzegovina (NPA Global Training Centre). Available at: www.gichd.org/publications/subject/animal-detection/training-of-mine-detection-dogs-in-bosnia-and-herzegovina-npa-global-training-centre-en. Accessed Mar 16, 2014.

    • Search Google Scholar
    • Export Citation
  • 13. Angle TC, Wakshlag JJ, Gillette RL, et al. The effects of exercise and diet on olfactory capability in detection dogs. J Nutr Sci 2014; 3: 15.

    • Search Google Scholar
    • Export Citation
  • 14. Sargisson RJ, McLean IG. The effect of reinforcement rate variations on hits and false alarms in remote explosive scent tracing with dogs. J ERW Mine Action 2010; 14: 6468.

    • Search Google Scholar
    • Export Citation
  • 15. Bromley SM. Smell and taste disorders: a primary care approach. Am Fam Physician 2000; 61: 427436.

  • 16. Medlink neurology clinical summaries. Drug-induced disturbances of smell and taste. Available at: www.medlink.com/medlinkcontent.asp. Accessed Oct 10, 2011.

    • Search Google Scholar
    • Export Citation
  • 17. Ship JA, Chavez EM. Special senses: disorders of taste and smell. In Silverman S, Eversole L, Truelove E, eds. Essentials of oral medicine. London: BC Booker, 2001;277288.

    • Search Google Scholar
    • Export Citation
  • 18. Ackerman BH, Kasbekar N. Disturbances of taste and smell induced by drugs. Pharmacotherapy 1997; 17: 482496.

  • 19. Doty RL, Shah M, Bromley SM. Drug-induced taste disorders. Drug Saf 2008; 31: 199215.

  • 20. Rogers J, Wiese BS, Rabheru K. The older brain on drugs: substances that may cause cognitive impairment. Geriatr Aging 2008; 11: 284289.

    • Search Google Scholar
    • Export Citation
  • 21. Bleasel AF, McLeod JG, Lane-Brown M. Anosmia after doxycycline use. Med J Aust 1990; 152: 440.

  • 22. Oxley J, Waggoner P. Detection of explosives by dogs. In: Marshall M, Oxley J, eds. Aspects of explosives detection. Amsterdam: Elsevier, 2009;2740.

    • Search Google Scholar
    • Export Citation
  • 23. Williams M, Johnston JM. Training and maintaining the performance of dogs (Canis familiaris) on an increasing number of odor discriminations in a controlled setting. Appl Anim Behav Sci 2002; 78: 5565.

    • Search Google Scholar
    • Export Citation
  • 24. Neff-Davis CA, Davis LE, Gillette EL. Metronidazole: a method for its determination in biological fluids and its disposition kinetics in the dog. J Vet Pharmacol Ther 1981; 4: 121127.

    • Search Google Scholar
    • Export Citation
  • 25. Caylor KB, Cassimatis MK. Metronidazole neurotoxicosis in two cats. J Am Anim Hosp Assoc 2001; 37: 258262.

  • 26. Bradley WG, Karlsson IJ, Rassol CG. Metronidazole neuropathy. Br Med J (Clin Res Ed) 1977; 2: 610611.

  • 27. Halloran TJ. Convulsions associated with high cumulative doses of metronidazole. Drug Intell Clin Pharm 1982; 16: 409.

  • 28. Ray RE, Holton JL, Lister T, et al. The glio-vascular toxicity of m-dinitrobenzene and related agents: modulation of toxicity by neuronal activation. Arch Toxicol Suppl 1996; 18: 140148.

    • Search Google Scholar
    • Export Citation
  • 29. Hawkes CH, Doty RL. General disorders of olfaction. In: The neurology of olfaction. Cambridge, England: Cambridge University Press, 2009;111152.

    • Search Google Scholar
    • Export Citation

Advertisement

Effects of oral administration of metronidazole and doxycycline on olfactory capabilities of explosives detection dogs

View More View Less
  • 1 Department of Clinical Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL 36489.
  • | 2 Department of Clinical Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL 36489.
  • | 3 Department of Canine Performance Sciences Program, College of Veterinary Medicine, Auburn University, Auburn, AL 36489.
  • | 4 Department of Clinical Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL 36489.
  • | 5 Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.

Abstract

OBJECTIVE To determine effects of oral administration of metronidazole or doxycycline on olfactory function in explosives detection (ED) dogs.

ANIMALS 18 ED dogs.

PROCEDURES Metronidazole was administered (25 mg/kg, PO, q 12 h for 10 days); the day prior to drug administration was designated day 0. Odor detection threshold was measured with a standard scent wheel and 3 explosives (ammonium nitrate, trinitrotoluene, and smokeless powder; weight, 1 to 500 mg) on days 0, 5, and 10. Lowest repeatable weight detected was recorded as the detection threshold. There was a 10-day washout period, and doxycycline was administered (5 mg/kg, PO, q 12 h for 10 days) and the testing protocol repeated. Degradation changes in the detection threshold for dogs were assessed.

RESULTS Metronidazole administration resulted in degradation of the detection threshold for 2 of 3 explosives (ammonium nitrate and trinitrotoluene). Nine of 18 dogs had a degradation of performance in response to 1 or more explosives (5 dogs had degradation on day 5 or 10 and 4 dogs had degradation on both days 5 and 10). There was no significant degradation during doxycycline administration.

CONCLUSIONS AND CLINICAL RELEVANCE Degradation in the ability to detect odors of explosives during metronidazole administration at 25 mg/kg, PO, every 12 hours, indicated a potential risk for use of this drug in ED dogs. Additional studies will be needed to determine whether lower doses would have the same effect. Doxycycline administered at the tested dose appeared to be safe for use in ED dogs.

Abstract

OBJECTIVE To determine effects of oral administration of metronidazole or doxycycline on olfactory function in explosives detection (ED) dogs.

ANIMALS 18 ED dogs.

PROCEDURES Metronidazole was administered (25 mg/kg, PO, q 12 h for 10 days); the day prior to drug administration was designated day 0. Odor detection threshold was measured with a standard scent wheel and 3 explosives (ammonium nitrate, trinitrotoluene, and smokeless powder; weight, 1 to 500 mg) on days 0, 5, and 10. Lowest repeatable weight detected was recorded as the detection threshold. There was a 10-day washout period, and doxycycline was administered (5 mg/kg, PO, q 12 h for 10 days) and the testing protocol repeated. Degradation changes in the detection threshold for dogs were assessed.

RESULTS Metronidazole administration resulted in degradation of the detection threshold for 2 of 3 explosives (ammonium nitrate and trinitrotoluene). Nine of 18 dogs had a degradation of performance in response to 1 or more explosives (5 dogs had degradation on day 5 or 10 and 4 dogs had degradation on both days 5 and 10). There was no significant degradation during doxycycline administration.

CONCLUSIONS AND CLINICAL RELEVANCE Degradation in the ability to detect odors of explosives during metronidazole administration at 25 mg/kg, PO, every 12 hours, indicated a potential risk for use of this drug in ED dogs. Additional studies will be needed to determine whether lower doses would have the same effect. Doxycycline administered at the tested dose appeared to be safe for use in ED dogs.

Contributor Notes

Dr. Jenkins' present address is 248th Medical Detachment (Veterinary Service Support), Fort Bragg, NC 28310.

Address correspondence to Dr. Lee-Fowler (tml0005@auburn.edu).