Effects of transdermal mirtazapine on hyporexic rhesus and cynomolgus macaques (Macaca mulatta and Macaca fascicularis)

J Med Primatol. 2021 Apr;50(2):128-133. doi: 10.1111/jmp.12512. Epub 2021 Feb 2.

Abstract

Background: Hyporexia and weight loss are important indicators of physical and psychological well-being in macaque colonies. An FDA-approved transdermal formulated Mirtazapine (MTZ) shows effectiveness in managing feline hyporexia. This study sought to determine its effectiveness as an appetite stimulant in macaques.

Methods: Fourteen macaques with idiopathic hyporexia, intractable to conventional management were treated with transdermal MTZ (0.5 mg/kg) topically administered to aural pinnae once daily for 14 days. Qualitative food consumption was monitored daily for 6 months. Body weights were collected prior to treatment, every 2 weeks for the first 6 weeks, 10 weeks, and 6 months post-treatment.

Results: Transdermal MTZ significantly reduced the frequency of hyporexia during treatment and monthly for 6 months. No significant increase in weight noted until approximately 6 months post-treatment.

Conclusions: Results from this study indicate that a short course of transdermal MTZ is an effective way to increase food consumption in macaques chronically.

Keywords: Macaque; anti-emetic; antidepressant; appetite stimulation; hyporexia; inappetence; mirtazapine.

MeSH terms

  • Administration, Cutaneous
  • Animals
  • Anorexia / drug therapy*
  • Appetite Stimulants / administration & dosage*
  • Female
  • Macaca fascicularis*
  • Macaca mulatta*
  • Male
  • Mirtazapine / administration & dosage*
  • Monkey Diseases / drug therapy*

Substances

  • Appetite Stimulants
  • Mirtazapine