Comparative Efficacy and Safety of Two Treatment Regimens with a Topically Applied Combination of Imidacloprid and Moxidectin (Advocate®) against Generalised Demodicosis in Dogs

Abstract

This laboratory study compared the efficacy of two treatment regimens using an imidacloprid (10%)/moxidectin (2.5%) topical formulation (Advocate, Bayer) on dogs with generalised demodicosis. Sixteen dogs were randomly allocated to two equal groups. One group was treated at 28-day intervals for 12 weeks and the second group at weekly intervals for 15 weeks. Mite numbers were estimated and demodectic lesions were evaluated on each dog before treatment and at approximately 28-day intervals thereafter. Consistently greater reduction in mite numbers was recorded for the weekly treatment regimen. Dogs treated at weekly intervals exhibited markedly fewer clinical signs and greater hair regrowth and weight gain than those treated at 28-day intervals. To assess the safety of a weekly treatment interval in dogs, a study was done in which the investigational compound was administered at weekly intervals at five times the recommended dose for a period of 16 consecutive weeks. Apart from transient erythema at the site of administration in one dog and scaliness of the skin in another, no clinical signs of toxicity could be observed. Assessment of 27 blood parameters indicated that only basophils were outside the reference values on days +13 and +69, during the safety trial period.

Treatment of canine demodicosis

“…The spot-on formulation containing 10 per cent imidacloprid and 2.5 per cent moxidectin (Advocate, Bayer; Prinovox, Virbac) is licensed for weekly use in severe cases of demodicosis and for monthly use in collies and related breeds. It has been evaluated in several studies and is recommended for the treatment of CGD due to its efficacy at weekly dosing (Heine and others 2005, Fourie and others 2009, Mueller and others 2009). After topical application it is rapidly distributed over the dog's skin within one day, with the moxidectin peak plasma level seen within four to nine days.…”

Molecular identification and phylogenetic study of Demodex caprae

“…With the pathogenicity of the mites parasitizing in animals like dog, goat, etc. and human being confirmed successively (Smith 1961;Sheahan and Gaafar 1970;Zhao et al 2010Zhao et al , 2011aZhao et al , b, 2012b, researchers have done some work in the ecology and cultivation of Demodex mites, as well as the therapy of demodicidosis (Heine et al 2005;Xhaxhiu et al 2009;Zhao et al 2009;Fourie et al 2009). It has been reported that the pathogenicity of Demodex is related to population.…”

Oral selamectin in the treatment of canine generalised demodicosis

“…Another study (Fourie and others 2009) compared the efficacy of a spot-on formulation containing 10 per cent imidacloprid and 2.5 per cent moxidectin in a monthly application regimen with a weekly regimen. In those studies, a correlation between the success rate and the frequency of application was seen, with weekly application being significantly better than monthly application.…”

“…Recently, a spot-on formulation containing moxidectin and imidacloprid has been approved as a monthly treatment for demodicosis in Europe. Reported success rates vary in different studies between 39.4 per cent (Mueller and others 2008) and 86.7 per cent (Heine and others 2005), but dogs with mild to moderate disease have been shown to respond better than dogs with severe demodicosis (Mueller and others 2008, Fourie and others 2009), and weekly administration resulted in higher remission rates than monthly administration (Paterson and others 2008). …”