I noticed improvement right away, after the first month with gradual improvements, at 1 year to 1 1/2 year she was completely stable. Occasional flare-ups (mild) certain times of the year.
I never did any blood tests as related to diagnosing her allergies. The dermatologist said we could skip, as her allergies appeared to be environmental. Just did the intradermal skin testing.
Each dogs allergens are unique, there is no blanket treatment. Not all allergies are seasonal, there are thousands of airborne allergens present year round , no matter what area you live in. The household dust mite, and dander (shedding off the skin of all living things) microscopic and impossible to avoid. I tried for 1 year with poor results, even had an air purifier and de-humidifier going. They both went to the Goodwill.
Evidence-Based Canine Allergy Treatment
Respit is discussed in comments starting on 6/14/10 of the above blog.
