Comparison of two shampoos for the treatment of canine Malassezia dermatitis: a randomised controlled trial.

Abstract

OBJECTIVES: Two antimicrobial shampoos for treatment of canine Malassezia dermatitis (CMD) were compared in a prospective, randomised, single-blinded, field clinical trial. METHODS: Sixty-seven dogs with pedal or generalised dermatitis associated with Malassezia overgrowth (MO) were treated with 3% chlorhexidine shampoo (3%CHX) or 2% miconazole-2% chlorhexidine shampoo (2%MIC/CHX) and evaluated for up to 6 weeks until cytological recovery. Pruritus, erythema, papules, greasy seborrhoea, scaling, malodour, excoriations, secondary hairloss, lichenification, hyperpigmentation and lesion extent were each scored on a 0-3 severity scale and combined making an aggregate score. RESULTS: Among 54 dogs with good treatment compliance, reduction of yeast counts by at least 88% was recorded in 21 of 22 dogs with 3%CHX and 30 of 32 dogs with 2%MIC/CHX. No significant difference was detected between products for yeast count reduction (P=0·592). Time to cytological recovery was not significantly different between groups (P=0·960). Lesion score was significantly reduced in both groups after treatment (72·5 ±25·7% with 3%CHX versus 78·7 ±22·3% with 2%MIC/CHX, P=0·309). Four dogs treated with chlorhexidine shampoo showed minor adverse effects. CLINICAL SIGNIFICANCE: In this study, 3%CHX was clinically as effective as 2%MIC/CHX for treatment of CMD.