Pilot study: antitussive effect of gefapixant in dogs with chronic cough.

Gefapixant is a P2X3 receptor antagonist approved for the treatment of chronic cough in humans, but its clinical use in dogs has not been reported. In this pilot study, gefapixant (2.09 ± 0.59 mg/kg twice daily) was administered to 10 dogs with refractory chronic cough. Eight dogs had paired owner-reported cough intensity visual analog scale (VAS) scores; mean scores decreased from 78 ± 15 to 52 ± 20 mm (P=0.0342). No serious adverse event was definitively attributed to gefapixant, although one dog with megaesophagus developed pneumonia. These preliminary observations warrant further controlled studies incorporating objective cough monitoring to determine the efficacy and safety of gefapixant in dogs.