If administered with other drugs, cyclosporine can interfere with (or be interfered with) other drugs. Probably the most well-known interaction is when administered with ketoconazole, cyclosporine levels will be increased. This drug interaction is sometimes purposely used to an advantage in that less cyclosporine can be used. Cyclosporine can inhibit p-glycoprotein—the multi-drug resistance efflux pump and enhance the absorption of drugs, such as digoxin and immodium. Cyclosporine concentrations can be increased when administered with other drugs, such as diltiazem, erythromycin and metoclopramide. Anticonvulsants, such as phenobarbital can decrease cyclosporine concentrations.

Immunotherapy is still the therapy of choice in our office for long-term treatment of atopy because long-term adverse effects of cyclosporine are yet to be determined. Cyclosporine is useful as the sole treatment for atopy or used initially in combination with immunotherapy to provide the patient with some relief. In the atopic patient with bacterial pyoderma, the pyoderma should be treated before starting cyclosporine therapy.

The drug is contraindicated in patients with known neoplasia and might potentiate subclinical toxoplasmosis in cats. Its main drawback, particularly in larger dogs, is its expense, but it is another option to offer the owner in the treatment of canine atopy.