Canis ISSN: 2398-2942

Therapeutics: non-bacterial infection

Contributor(s): Kyle Braund, Maggie Fisher, Chris Taylor, Lauren Trepanier

Non-bacterial infections

Antifungal agents

Topical agents
  • Treatment of fungal infections of skin, ear and eye.
Skin infections
  • Successful treatment depends on management which limits infection, eg grooming, clipping, isolation, cleansing agents for animal and environment.
  • Systemic agents may be used also.

Pruritic skin disease


Ear infections

  • Usually combination preparations.


Eye infections

  • Conditions may be superficial, eg mycotic keratitis Keratitis or intra-ocular, eg mycotic endophthalmitis Endophthalmitis/Panophthalmitis.
  • Most topical preparations have poor corneal penetration, so systemic preparations preferred.


Systemic agents

  • Griseofulvin Griseofulvin.
  • For dermatophyte infections.
  • Deposited in keratin precursor cells → stratum corneum of skin, hair and nails → prevents fungal invasion of new cells.
  • Absorption enhanced by administration with fatty meal.
  • Treatment usually minimum 3-4 weeks → 12 weeks.
    May be teratogenic: avoid handling by pregnant women


  • Interfere with biosynthesis of ergosterol.
  • Fungistatic.
  • Broad spectrum.
  • Clotrimazole Clotrimazole.
  • Topical.
  • Malassezia infection Skin: malassezia disease (as 1% solution).
  • Miconazole Miconazole.
  • Topical.
  • Too toxic for treatment of systemic fungal infections.
  • KetoconazoleKetoconazole.
  • Active against fungi and yeasts, some gram-positive bacteria.
  • For systemic candidiasis and refractory dermatophytoses.
  • Administration with food may → nausea. Do not administer with antacids, which can reduce its absorption.
  • Interferes with mammalian adrenal and gonadal steroid synthesis → alternative treatment for Cushing's disease (hyperadrenocorticism Hyperadrenocorticism ).

    May be teratogenic; prolonged administration may result in liver damage
  • ItraconazoleItraconazole.
  • Systemic candidiasis, refractory dermatophytoses, sytemic fungal infections.

    Do not administer with antacids, which can reduce its absorption.
  • Fluconazole Fluconazole.
  • Systemic candidiasis, refractory dermatophytosis, systemic fungal infections.
  • Absorption not affected by antacids.
  • NystatinNystatin.
  • Gastrointestinal candidiasis Candida albicans.
  • AmphotericinAmphotericin B.
  • Against yeasts and fungi. Used for life-threatening or refractory systemic fungal infections.
  • Nephrotoxic. Requires saline diuresis. Liposomal formulation markedly reduces nephrotoxicity.

Antiviral agents

  • Used mainly in ophthalmology.

Eye infections

Antiprotozoal agents



  •  Neospora caninum Neospora caninum.
  • Clindamycin Clindamycin.
  • Co-trimazine (trimethoprim + sulfadiazine)- see above, also in combination with pyrimethamine.


  • Clindamycin Clindamycin.
  • Co-trimazine (trimethoprim + sulfaziazine)- see above, also in combination with pyrimethamine.


Further Reading


Refereed papers

Other sources of information

  • Lappin M R (2000) Protozoal and miscellaneous infections. In: Textbook of Veterinary Internal Medicine. 5th edn. Ettinger S J & Feldman E C (eds). W B Saunders, Philadelphia. pp 408-417.
  • Taboada J (2000) Systemic mycoses. In: Textbook of Veterinary Internal Medicine.5th edn. Ettinger S J & Feldman E C (eds). W B Saunders, Philadelphia. pp 453-476.
  • Plumb D C (1999) Veterinary Drug Handbook. 3rd edn. Iowa State University Press, Ames, Iowa.