Inflammatory mediators like histamine cause cutaneous nerve stimulation which leads to pruritus sensation and scratch.Affected areas show erythema ( redness ) or rashes.In chronic patients alopecia and darkness of the skin can be seen.

Common Causes:

Most often pruritus in dogs is caused by :

1-Ectoparasites:  flea, lice,,scabies, insect biting,demodicosis

2- Infection agents: Staphylococcal pyoderma , Malassezia dermatitis

3-Allergies: contact,food and atopic dermatitis

Diagnosis:

On the basis of examination, distribution of lesions,flea comb,skin scraping or cytology test,therapeutic trial, skin allergy test,rarely skin biopsy diagnosis is done.

Treatment:

It is done on the basis of diagnosis such as anti-flea spray for flea infestation.

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