Cyclosporine is a cyclic undecapeptide from an extract of soil fungi. It is a powerful immunosupressant with a specific action on T-lymphocytes. It is used for the prophylaxis of graft rejection in organ and tissue transplantation. Pharmacologic action of cyclosporine includes the following:
- Antifungal agent - destroys fungi by suppressing their ability to grow or reproduce.
- Dermatologic agent - treats or prevents skin disorders.
- Enzyme Inhibitor - combines with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
- Immunosuppressive agent - suppresses immune function by one of several mechanisms of action.
- Antirheumatic agent - treats rheumatoid arthritis.
In dogs the drug is used for the control of atopic dermatitis weighing at least 4 pounds body weight. Cyclosporine is not toxic to cta or dog kidneys or liver unless extremely high blood concentrations are maintained. If these high concentrations are maintained for several weeks or months, opportunistic bacterial and fungal infections can occur. Cyclosporine can cause tumors in cats and dogs, particularly lymphomas.