Around 15 percent of dogs and cats in the United Sates have allergies, and the symptoms and causes vary 
drastically, says Trish Ashley, DVM, of Springfield, Oregon. Here’s how to pinpoint the culprit—from pollen to protein—and find a natural remedy to match.
Problem: Proteins in flea saliva can cause itching, especially around the lower body, tail, and hind legs.
Solution: Natural remedies that use chrysanthemum-based insecticides, a citrus byproduct called D-limonene, or diatomaceous earth (a gentle sedimentary rock).
Try: St. Gabriel Organics Insect Dust
Problem: Allergies to pollen and mold spores cause itching (which can lead to fur loss), ear infections, runny eyes, and sneezing.
Solution: Formulas made with herbs like ginkgo, ephedra, stinging nettle, or reishi.
Try: Doc Ackerman’s Allergy Relief Formula
Problem: Food allergy symptoms are similar to inhalant allergy symptoms. The most common pet allergens are proteins such as beef, dairy, chicken, or lamb.
Solution: Feed your pet one type of ingredient for a couple of weeks to find out which foods the pet can’t tolerate.
Try: The Honest Kitchen dog and cat food