A randomized double‐blinded placebo‐controlled study to evaluate an effective ciclosporin dose for the treatment of feline hypersensitivity dermatitis

Background –  Hypersensitivity dermatitides (HD) are frequently suspected in cats, but there are few clinical studies on safe and effective treatments in the published literature. Objectives –  To establish a safe and effective dose of ciclosporin in the treatment of feline HD. Animals –  One hundred client‐owned cats with feline HD. Methods –  Double‐blind study, with cats randomly assigned to receive ciclosporin at either 7.0 mg/kg once daily ( n  = 33) or 2.5 mg/kg once daily ( n  = 32) or a placebo ( n  = 35) for 6 weeks. Results –  Mean Total Lesion Scores with 7.0 mg/kg ciclosporin were significantly lower than with 2.5 mg/kg ciclosporin ( P  = 0.0047) or placebo ( P  = 0.0003) at study end. Individual Total Lesion Scores improved by >50% in 70% of the 7.0 mg/kg group, compared with 47% in the 2.5 mg/kg group and 23% in the placebo group ( P  = 0.0006). The investigators’ Global Assessment of Improvement was ‘excellent’ or ‘good’ in 61% of cats treated with 7.0 mg/kg ciclosporin, compared with 47% of cats given 2.5 mg/kg and 23% given placebo. The improvement in Investigator Pruritus Scores was significantly greater in cats treated with 7.0 mg/kg ciclosporin (54%) compared with both 2.5 mg/kg ciclosporin (32%; P  = 0.0232) and placebo (21%; P  = 0.0063). Mild gastrointestinal disorders were the most common adverse events, but these did not require cessation of therapy. Conclusions and clinical importance –  Results suggest that 7.0 mg/kg ciclosporin once daily in food or per os for 6 weeks is effective and well tolerated in feline HD.