Tacrolimus for Veterinary Use

Therapeutic Class: Calcineurin inhibitor

Species: Dogs and cats

May Be Prescribed For: Keratoconjunctivitis Sicca, Atopic dermatitis.

Tacrolimus is one of a group of relatively new drugs called Calcineurin inhibitors. These drugs are anti-inflammatory, and immunosuppressive or immunomodulatory. The mechanism of action is through the inhibition of calcium-dependent pathways that effect the enzymatic action of Calcineurin. This, in turn, blocks the proliferation of T-lymphocytes and cytotoxic cells. When one reviews the human literature, Calcineurin inhibitors are investigated widely for use in atopic dermatitis and in organ transplant recipients. At the present time, veterinary use of tacrolimus is primarily for keratoconjuctivitis sicca in dogs and cats and immune-mediated dermatologic diseases.

Keratoconjunctivitis sicca due to decreased tear production is primarily an immune-mediated disease of the lacrimal glands. It is seen more commonly in dogs than in cats. Cyclosporine and tacrolimus are the two drugs most commonly used to stimulate tear production. Cyclosporine has been the standard drug for years although topical ophthalmic tacrolimus is thought to be considerably more effective; as a result it may be useful in animals that are refractory to cyclosporine. Animals with immune-mediated KCS will need to be on treatment for the rest of their lives.

Topical tacrolimus also may be useful in localized treatment of atopic dermatitis, pemphigus, lupus erythematosus complex, miliary dermatitis, and eosinophilic granuloma complex.

• Tacrolimus is very well-tolerated in the ophthalmic treatment of KCS.

• Tacrolimus generally is well-tolerated for the localized topical treatment of dermatologic problems. GI symptoms may be encountered from ingestion of the topical ointment (licking).

Only topical use of tacrolimus is recommended currently. There is not sufficient information regarding systemic use.

No information regarding drug interactions was found in the literature.