Use of antihistamines to control pruritus in atopic dogs

Abstract

In an open uncontrolled study, 30 dogs with atopy were given six different antihistamines over a period of 10 weeks. During the first six weeks the dogs were given each of the antihistamines, hydroxyzine, trimeprazine, chlorpheniramine, clemastine, promethazine and cyproheptadine for a seven-day period. The order of drug administration was randomised in each case. After assessment of clinical improvement, based on the drug's ability to control pruritus, the most successful drug was given for a further four weeks. Where several drugs performed equally well in the control of signs, the second drug was selected on cost, ease of administration and lack of side effects. More than 60 per cent of the dogs benefited from antihistamine therapy and few side effects were noted. Hydroxyzine in this trial, proved to be the most effective antihistamine in controlling pruritus, although all of the drugs were shown to have the ability to control pruritus in some dogs.

Retrospective survey of allergen immunotherapy in canine atopy

“…An advantage of this approach is that it provides an accurate indication of the likely long-term outcome of immunotherapy in referral cases. The overall success rate of 61.3 per cent, compares favourably with that of other steroid-sparing treatments such as essential fatty acids (Sture and Lloyd 1995) and antihistamines (Paterson 1994). Two dogs required only a single course of treatment.…”

Results of allergen‐specific immunotherapy in 117 dogs with atopic dermatitis

“…It is most commonly treated with glucocorticoids, antihistamines and fatty acid supplementation (Olivry and Mueller 2003), but the only specific treatment is allergenspecific immunotherapy (Griffin and Hillier 2001). In recent years several studies have described the efficacy of this treatment (Gosselin and others 1983, Willemse and others 1984, Walton Angarano and Macdonald 1992, Scott and others 1993, Mueller and Bettenay 1996, Nuttall 1998, Zur and others 2002, which is not associated with the adverse effects commonly caused by the administration of glucocorticoids and is more effective than antihistamines, fatty acids or shampoo therapy (Paterson 1994, Scott and others 2001, Mueller and others 2004. In human medicine the success rate of allergen-specific immunotherapy is influenced by factors such as the age of the patient and how long the patient has suffered the disease before the treatment was applied (Des Roches andothers 1996, Durham andothers 1999).…”

Antihistamines in the management of allergic pruritus in dogs and cats

“…For instance, alfhough terfenadine markedly inhibited allergen-induced wheal formation in the skin of Ascaris-hypersensitive dogs (Awouters and others 1986), the same dose of the drug was ineffective for treating pruritus in atopic dogs (Scott and others 1994). Similarly, although chlorpheniramine and clemastine failed to inhibit allergen-induced wheal formation in the skin of Ascaris-hypersensitive dogs (Awouters and others 1986), both antihistamines were effective for controlling pruritus in many atopic dogs (Scott and Buerger 1988, Paradis and others 1991a,b, Miller and others 1993, Paterson 1994. Loratadine markedly inhibited degranulation of dispersed canine mast cells (Garcia and others 1997), but was ineffective in allergic dogs (Paradis 1996).…”

“…The response of pruritic dogs and cats to the different antihistamines is unpredictable (Scott and Buerger 1988, Paradis and others 1991b, Paterson 1994, Scott and others 1998. The clinician must be prepared to try several antihistamines in each patient in order to find one that is most effective.…”