PUBLISHED April 11, 2015

Cats' allergy symptoms can manifest as miliary dermatitis, which shows up as little scabs or missing hair, typically around the head and neck. Photogrpah by Amy White & Al Petteway, Nat Geo Image Collection

Spring has sprung, and with it the return of warmer weather, longer days, and one decidedly unwelcome guest: allergies.

It's also the perfect season to turn the tables and look at allergies from our pets' point of view. So for Weird Animal Question of the Week, we're responding to National Geographic's own Emily Tye, who asks: "Can catsbe allergic to dogs, or vice versa?"

We also wonder—can they be allergic to us?

"The answer to all of these is yes," says Raelynn Farnsworth, of Washington State University's College of Veterinary Medicine. (See " Coughing Cats May Be Allergic to People, Vets Say.")

"It's rare, but dogs can be allergic to cat dander and people dander and vice versa. For everything."

Dander is made up of tiny cells shed from hair, fur, or feathers—and though you mostly hear it in relation to pets, humans produce it, too. Other common pet allergies include flea saliva and certain foods.

Sick as a Dog

For dogs, the most common clinical signs are skin inflammation and itching, Farnsworth says. Other symptoms may include sneezing and runny noses. ( Take National Geographic's dog quiz.)

Cats' allergy symptoms can manifest as miliary dermatitis, which shows up as little scabs or missing hair, typically around the head and neck area, though it can happen elsewhere, she says.

It's always important to observe how long symptoms occur in your pet—for instance, year-round symptoms may indicate a food allergy or reaction to something else in their environment that's not seasonal.

Luckily, pets can be tested for a variety of environmental allergens—both seasonal and non-seasonal, says Christine Cain, of the University of Pennsylvania School of Veterinary Medicine.

"We routinely test dogs for reactions to cat dander," she says. "This includes a small amount of allergen placed under the skin to test for reactions, just like in human allergy testing," Cain says.

Generally, veterinarians will look for common allergens "like dust mites and human dander, or things we encounter in the environment like feathers, sheep wool, or pollens," says Washington State University's Farnsworth.

Those are the usual suspects, but as with us, Farnsworth says, pets can be allergic to anything, and it can be difficult to figure out the culprit with general testing.

It's Not Me, It's You

So what if your pet is allergic to you?

"It always makes owners kind of sad if their reaction is to human dander," Cain says, but happily the two of you don't have to part. (See "Why Do We Get Allergies?")

"If we have a patient that reacts to human dander, usually they react to other allergens as well," she says.

That means your vet can treat the pet's allergy, either with allergy shots or oral drops that contain small amounts of the problem allergens. This retrains your pet's system to ignore the allergen.

Of course, the cat might always be faking an allergy in hopes you'll get rid of the dog.