Effect of Gabapentin Administered With Prednisolone, Ciclosporin or a Placebo on Clinical Outcomes and Motor Activity in Cats With Atopic Skin Syndrome: A Prospective, Blinded, Placebo-Controlled Study.

Abstract

Background: Gabapentin reportedly decreases central sensitisation, a disorder associated with chronic pruritus in humans, although this is not well documented in cats. Its combined use with the standard antipruritic therapy for feline atopic skin syndrome (FASS) is not yet described.

Objectives: To evaluate the impact of prednisolone, ciclosporin or placebo, with or without gabapentin, on lesional scores and actimetry in FASS cats.

Animals: Twenty-six cats from a laboratory colony with naturally acquired FASS.

Methods and materials: Following a 12-week washout period, cats were allocated to one of three groups: prednisolone (1 mg/kg, n = 9), ciclosporin (7 mg/kg, n = 8) and placebo (Avicel, n = 9). Treatments were administered orally, once daily for 5 weeks (Week [W]0 to W4), then combined with gabapentin (10-15 mg/kg) for another 3 weeks. The Feline Dermatitis Extent and Severity Index (FeDESI) was assessed at baseline and W2, W4 and W7. Actimetry was recorded and analysed over weekend (WE) time points. A repeated-measures generalised mixed model was applied using the zero-inflated negative binomial (FeDESI) or log-normal (actimetry) distribution (α = 0.05).

Results: Prednisolone alone significantly improved FeDESI (p = 0.008), while ciclosporin required the addition of gabapentin to achieve a significant effect (p < 0.034). Gabapentin decreased FeDESI scores in all groups (p < 0.001) and demonstrated the highest incidence rate ratio (2.59) compared to placebo. Improvements in FeDESI were associated with significant (corresponding in intensity) decreases in motor activity.

Conclusions and clinical relevance: Gabapentin, particularly when combined with prednisolone or ciclosporin, may reduce lesional score and actimetry-assessed itch in FASS cats, suggesting a potential central sensitisation in some cats.