This article is from the Canine Allergies FAQ, by Cheryl Minnier with numerous contributions by others.
The most common medical complaint we see in dogs is skin or ear
related. Unlike humans who react to allergens with nasal symptoms,
dogs react with skin problems. These problems may range from poor coat
texture or length, to itching and chewing, to hot spots and self
mutilation. Allergies may also play a part in chronic ear infections.
To make matters more difficult to diagnose and treat, thyroid disease
may add to the problem as well.
In order to overcome these frustrating symptoms your approach needs to
be thorough and systematic. Shortcuts usually will not produce results
and only add to owner frustration. This article will cover diagnosing
and treating; inhalant, food, and flea allergies. I will also briefly
discuss thyroid disease and immune mediated disorders.
Remember, your best source of information is your vet. Many vets are
now recognizing the need for holistic allergy treatment instead of the
tried and true (and possibly ineffective or dangerous) standby of
corticosteroids. If your vet is not helpful, keep looking until you
find someone you are comfortable with. You need to remember though,
that the success or failure of treatment will rest mainly on you.
There is no magic pill to deal with these problems. Unfortunately,
there is also no "cure", only systematic treatment options. Much of
the information below is taken from "Guide to Skin and Haircoat
Problems in the Dog" by Lowell Ackerman, DMV.