ISSN 2398-2942      

Therapeutics: immune system


Synonym(s): Immunomodulatory drugs


  • Glucocorticoids (steroids, eg prednisolone) Therapeutics: glucocorticoids remain the mainstay of immunosuppressive therapy in veterinary medicine as a result of their broad efficacy and relatively low cost. Both short-term and long-term prednisolone therapy is associated with significant risk of side-effects.
  • The response to glucocorticoids is variable within and between species. Cats require higher doses than dogs to have the same effect, and larger breed dogs tend to suffer more significant side- effects. In humans, glucocorticoid resistance is documented in up to 30% of patients, and has also been documented in veterinary patients with cancer.
  • There are several scenarios in which an alternative immunosuppressant strategy is required, and there are now several alternative drugs available.
  • Examples of immunosuppressive agents:
    • Azathioprine
    • Chlorambucil
    • Ciclosporin/Cyclosporine
    • Cyclophosphamide
    • (Gold salts - limited use, specific indications only, rarely used)
    • Human intravenous immunoglobulin (hIVIg)
    • Leflunomide
    • Methotrexate
    • Mycophenolate mofetil
    • Prednisolone
    • (Sulfasalazine - limited use, specific indications only, occasionally used for inflammatory large bowel disease in dogs)
    • Vincristine
Many of these drugs are not licensed in veterinary species, and licensing varies across the world. It is therefore advisable to check with the local authority prior to administration.


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Further Reading


Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Vessieres F, Cianciolo R E, Gkoka Z G et al (2019) Occurrence, management and outcome of immune-complex glomerulonephritis in dogs with suspected glomerulopathy in the UK. JSAP 60(11), 683-690 PubMed.
  • Swann J W, Garden O A, Fellman C L et al (2019) ACVIM consensus statement on the treatment of immune-mediated hemolytic anemia in dogs. J Vet Int Med 33(3), 1141-1172 PubMed.   
  • Cummings F O & Rizzo S A (2017) Treatment of presumptive primary immune-mediated thrombocytopenia with mycophenolate mofetil versus cyclosporine in dogs. JSAP 58 (2), 96-102 PubMed.   
  • Sato M, Veir J K, Legare M et al (2017) A retrospective study on the safety and efficacy of Leflunomide in dogs. J Vet Int Med 31 (5), 1502-1507 PubMed.  
  • Wallisch K & Trepanier L A (2015) Incidence, timing, and risk factors of azathioprine hepatotoxicosis in dogs. J Vet Int Med 29 (2), 513-518 PubMed.   
  • Yau V K & Bianco D (2014) Treatment of five haemodynamically stable dogs with immune-mediated thrombocytopenia using mycophenolate mofetil as single agent.JSAP55, 330-333 PubMed.
  • Balog K, Huang A A, Sum S O et al  (2013) A prospective randomized clinical trial of vincristine versus human intravenous immunoglobulin for acute adjunctive management of presumptive primary immune-mediated thrombocytopenia in dogs. J Vet Int Med 27, 536-541 PubMed.   
  • Dandrieux J, Noble P-J, Scase T J et al (2013) Comparison of a chlorambucil-prednisolone combination with an azathioprine-prednisolone combination for treatment of chronic enteropathy with concurrent protein  losing enteropathy in dogs; 27 cases (2007-2010). JAVMA 242, 1705-1714 PubMed.  
  • Segev G, Cowgill L D, Heiene R et al (2013) Consensus recommendations of immunosuppressive treatment of dogs with glomerular disease based on established pathology. J Vet Int Med 27, S44-S54 PubMed.    
  • Wang A, Smith J R & Creevy K E (2013) Treatment of canine idiopathic immune-mediated haemolytic anaemia with mycophenolate mofetil and glucocorticoids: 30 cases (2007 to 2011). JSAP 54 339-404 PubMed.   
  • West L D & Hart J R (2013) Treatment of idiopathic immune-mediated hemolytic anemia with mycophenolate mofetil in five dogs. J Vet Emerg Crit Care 24 (2), 226-231 PubMed.  
  • Archer T M, Fellman C L, Stokes J V et al (2011) Pharmacodynamic monitoring of canine T‐cell cytokine responses to oral cyclosporine. J Vet Int Med 25, 1391-1397 PubMed.  
  • Piek C J, van Spil W E, Junius G et al (2011) Lack of evidence of a beneficial effect of azathioprine in dogs treated with prednisolone for idiopathic immune-mediated hemolytic anemia: a retrospective cohort study. BMC Vet Res 7 (1), 15 PubMed.
  • Colopy S A, Baker T A & Muir P (2010) Efficacy of leflunomide for treatment of immune-mediated polyarthritis in dogs: 14 cases (2006-2008). JAVMA 236 (3), 312-318 PubMed.  
  • Bianco D & Hardy R M (2009) Treatment of Evans' syndrome with human intravenous immunoglobulin and leflunomide in a diabetic dog. JAAHA 45, 147-150 PubMed.
  • Bianco D, Armstrong P J & Washabau R J et al (2009) A prospective, randomized, double-blinded, placebo-controlled study of human intravenous immunoglobulin for the acute management of presumptive primary immune-mediated thrombocytopenia in dogs. J Vet Int Med 23, 1071-1078 PubMed.        
  • Burkitt J M, Sturges B K, Jandrey K E et al (2007) Risk factors associated with outcome in dogs with tetanus: 38 cases (1987-2005). JAVMA 230 (1), 76-83 PubMed.
  • Allenspach K, Rüfenacht S, Sauter S et al (2006) Pharmacokinetics and clinical efficacy of cyclosporine treatment of dogs with steroid‐refractory inflammatory bowel disease. J Vet Int Med 20 (2), 239-244 PubMed.    
  • American Animal Hospital Association (AAHA) Canine Vaccine Task Force, Paul M A, Carmichael L E et al (2006) 2006 AAHA Canine Vaccine Guidelines. J Am Anim Hosp Assoc 42 (2), 80-89 PubMed.
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  • Schultz R D (2006) Duration of immunity for canine and feline vaccines: a review. Vet Microbiol 117 (1), 75-79 PubMed.
  • Steffan J, Favrot C & Mueller R (2006) A systematic review and meta-analysis of the efficacy and safety of cyclosporin for the treatment of atopic dermatitis in dogs. Vet Dermatol 17, 3-16 PubMed.
  • Gaskell R M, Gettinby G, Graham S J et al (2002) Veterinary Products Committee working group report on feline and canine vaccination. Vet Rec 150 (5), 126-134 PubMed.
  • Olivry T, Rivierre C, Jackson H A et al (2002) Cyclosporine decreases skin lesions and pruritus in dogs with atopic dermatitis: a blinded randomized prednisolone-controlled trial. Vet Dermatol 13, 77-87 PubMed.  
  • Mason N, Duval D, Shofer F S et al (2001) Cyclophosphamide exerts no beneficial effect over prednisone alone in the initial treatment of acute immune-mediated hemolytic anemia in dogs: a randomized controlled clinical trial. J Vet Int Med 17, 206-212 PubMed.
  • Burgess K, Moore A, Rand W et al (2000) Treatment of immune-mediated hemolytic anemia in dogs with cyclophosphamide.J Vet Int Med14, 456-462 PubMed.    
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