VPT 311: General and Systemic Veterinary Pharmacology (2+1)

IMMUNOSUPPRESSANTS 

• These are agents known to suppress the immune response on administration. In human beings they are very commonly used in transplants to prevent graft rejection and in the treatment of autoimmune diseases. In veterinary practice too, they are very useful.
• Glucocorticoids are the most commonly used immunosuppressive agents. It is used for immune mediated skin disorders.
• Cyclophosphamide, an alkylating agent, is used in combination with glucocorticoids for severe cases of autoimmnune diseases such as systemic lupus erythematosus, pempighus, rheumatoid arthritis.The side effects include haemorrhagic cystitis, fibrosis of the bladder, bone marrow suppression etc.
• Chlorambucil is slower acting and less toxic. It is administered alternately with glucocorticoids.
• Azathioprine is more commonly used for pemphigus.
• Cyclosporine which is most commonly used in man for graft rejection, may also be used in animals to prevent pempighus, lupus etc. It is potentially nephrotoxic, hepatotoxic, toxic to alimentary tract, and bone marrow suppression. It blocks the proliferation of activated T lymphocytes, by inhibiting interleukin-2, gene activation and RNA transcription. It can be used for Keratoconjunctivitis sicca in dogs.
• Dapsone used as an antibacterial for treating leprosy in man, has been found to inhibt chemotaxis, degranulation of mast cells and inhibit IgG, IgA, prostaglandins and also T cell responses. It is also used for canine pemphigus and lupus erythematosus and allows for decrease in the dose of glucocorticoids.