Pharmacological appetite stimulation: rational choices in the inappetent cat

Inappetence is a commonly encountered problem in feline medicine. Primary goals in managing the inappetent or anorectic cat are to diagnose and treat the underlying disease and reinstate adequate nutrition.

As cats are intolerant of prolonged periods of inadequate nutritional intake, especially given their propensity to develop hepatic lipidosis, their increased requirements for amino acids, and inability to slow their rate of gluconeogenesis, symptomatic therapy and nutritional support is often required during diagnostic investigations.

Most cats presenting with reduced food intake will be suffering from an underlying systemic disease, and so the mechanism of action, pharmacokinetics and contraindications of appetite-stimulating medications will need to be considered in each case to ensure rational use of these agents. Pharmacological appetite stimulation should never replace monitoring and ensuring adequate caloric intake, and may not be appropriate in some cases, such as critically ill or severely malnourished patients.

While there are no medications approved specifically for the treatment of anorexia in cats, some drugs have proven efficacious in the clinical field. Although several agents have been used historically for appetite stimulation, due to potential side effects and/or lack of efficacy or predictability only cyproheptadine and mirtazapine can currently be recommended for use.