A previous study (W08-020) funded by the Winn Feline Foundation on the pharmacodynamic and pharmacokinetic aspects of mirtazapine demonstrated the appetite stimulating properties of mirtazapine and also determined the appropriate dose rates and intervals for cats that are healthy and cats with CKD. The investigators in that study followed with this placebo-controlled, double-masked crossover clinical trial to evaluate the effects mirtazapine on bodyweight, appetite, and vomiting in cats with CKD. In a randomized trial, eleven cats with stable CKD received 1.88 mg mirtazapine or placebo orally every other day for three weeks. Weight gain was noted in 91% of the cats with CKD during the mirtazapine phase, while 82% of the cats lost weight during the placebo phase. The appetite score and activity score were both significantly increased when the cats received mirtazapine. The appetite score was found to be increased in 91% of cats and the activity score was increased in 55%. A statistically significant decrease in vomiting was also noted.
The authors concluded that mirtazapine is an effective appetite stimulant and anti-emetic for cats with CKD. Mirtazapine can aid in the nutritional management of these cases and, therefore, potentially improve their quality of life.
