What Is Dander? What Allergists Need You to Know

Updated: Jul. 14, 2021

Here's why the dander from cats and dogs (or horses, hamsters, and other animals, for that matter) can trigger a frenzy of miserable allergy symptoms.

Could I be allergic to animals?

No doubt you’ve heard about the connection between dander and allergies. Dander is one of those terms that describes the fur of fluffy cats and long-haired dogs, right? Not exactly.

If you’re allergic to pet dander, it doesn’t matter if you’re getting up close and personal with a hairless cat, a curly poodle, or a short-haired dachshund.

Any mixed breed or purebred cat or dog, whether they have long, short, or no hair, could evoke a drawn-out sniffle session with watery and itchy eyes.

Here’s what you need to know about pet dander, how to treat it, and how to manage symptoms, so you can still hang around your furry (or hairless) friends.

What are allergies?

Pet dander is one of those allergens that can cause allergic rhinitis or hay fever. More than 19 million adults in the United States have hay fever, according to the Asthma and Allergy Foundation of America (AAFA).

People with hay fever might be allergic to one or a combination of allergens such as pollen, dust, dust mites, mold, or animal dander.

If you’re allergic to one of these allergens and get a whiff of one, your body sees it as an unwelcome guest and tries to give it the boot. Your immune system prepares to defend itself by creating antibodies called immunoglobulin E (IgE).

Your body also releases histamines and other chemicals that cause irritating symptoms in the nose, eyes, ears, and throat.

Each type of IgE has a specific detector for each type of allergen. This explains why some people are allergic to cat and dog dander and not dust, and why some people have allergic reactions to multiple allergens.

Why do some people have allergies?

It’s still a mystery why the body’s immune system sees things like animal hair or pollen as foreign invaders and overreacts. Just as unclear is why some people have allergic reactions while others escape the sniffles.

Allergists do know that a family history of allergies and asthma is a risk factor, though.

Although people often first notice allergies in childhood or adolescence, they can develop at any age, says Tina Sindher, MD, an allergist at Standford Health Care in San Jose, California.

About one-third of people with allergies are also allergic to cats and dogs. No offense to fabulous felines, but cat allergies are twice as common as dog allergies.

Dog Scratching at homeCatherine Falls Commercial/Getty Images

What is dander?

It certainly seems legit to blame animal hair (especially the fluffy and long-haired cats and dogs) for triggering an allergic reaction. Surprisingly, it’s not those furry coats. The sneezing and itchy eyes that ensue after hanging out with your furry friends are actually from dander.

So, what is cat dander? And what is dog dander, you ask? Dander is made up of tiny flecks of skin shed by animals with hair, fur, or feathers. (Yes, birds shed dander too.)

It’s the protein found in pet dander, saliva, and urine that is the real culprit.

Here’s the caveat, even if you don’t go near the animal, you can still have an allergic reaction, though.

Let’s say you’re visiting your friend who has a cat. As soon as you arrive, it runs to another room to hide. Phew! Now you don’t have to worry. Yet, within minutes, you’re emptying the box of tissues.

What gives? You didn’t even go near the cat. Blame it on those lightweight tiny flecks of dander that linger in the air you’re breathing.

And even if your friend puts the cat in another room hours before you arrive, you’re probably still going to have an allergic reaction because the dander is everywhere—it settles in the carpet, on the furniture, on your friend’s clothing, just to name a few.

What are the symptoms of pet allergies?

You already know the main reaction—sneezing. But there’s more to allergy symptoms than nose-related ones.

When an allergen, in this case, pet dander, makes its way into the nasal passage, inflammation occurs and can produce the following symptoms:

  • Sneezing or a runny or stuffy nose
  • Watery, red, or itchy eyes
  • Puffy eyes
  • Itchy nose, throat, or ears
  • Throat clearing (from mucus)
  • Facial pain (from nasal congestion)
  • Coughing
  • Chest tightness
  • Shortness of breath and wheezing
  • Watery, red, or itchy eyes
  • Skin rash or hives (from being scratched by the pet)

How are pet allergies diagnosed?

If you sneeze or get teary-eyed around pets, you may wonder why allergy testing is necessary. The allergy symptoms mentioned above could show up in a host of other conditions, too.

“Some folks might have a virus, a sinus infection, or even acid reflux,” says Daniel Sullivan, MD, an allergist, otolaryngologist, and surgeon specializing in allergies at the Health First Medical Group in Melbourne, Florida.

Or you might mistake a pet allergy for a pollen one since you’re sneezing after exposure to a cat or dog who played outside or rolled in pollen. When in fact, you might just be allergic to pollen—or both.

“That’s where allergy testing is very handy, and thorough physical exam,” adds Dr. Sullivan.

Allergists give a virtually painless allergy skin test. A tiny amount of allergen is dropped on your skin, and the area is gently scratched. If redness and swelling appear at the test site, you’re allergic.

(Here’s what allergists say about at-home allergy tests)

How to help prevent pet dander allergies

The best way to avoid a pet dander allergy is to avoid contact with them or where they live. Though that’s pretty much impossible, and if you’re an animal lover, not interacting with animals is a horrible prospect.

Luckily, you have a myriad of options that can help eliminate pet allergies or at least mitigate the severity of allergic reactions. Let’s break it down and explain how it works into the following categories.

Manage pet dander exposure

If you know you have an allergy to cats or dogs, keep them out of your bedroom at all times. It sounds heartless, especially when you love snuggling with your pet, but it could really help you sleep better if there’s no direct exposure to allergens and sneezing all night.

Now, that’s not a guarantee there won’t be any allergens here and there, but it will cut down your exposure. To further cut down allergens, consider running an air purifier.

HEPA filters work the best, but they will fill with pet hair before getting any type of filtration if you have a pet in the home,” says Dr. Sullivan.

An air purifier in the bedroom where pets aren’t allowed is more effective, he says. Use HEPA filters in air conditioners and forced-air heating, and cover your bedroom vents with cheesecloth to help capture allergens before they hit your nose.

Don’t pet, hug, or kiss a cat or dog. But if you can’t resist, be sure to wash your hands with soap and water. Chances are, if you just pet the cat or dog, you could walk away without any symptoms.

But if you rubbed your face next to theirs, the allergens are probably in your hair, on your face, and clothes, and washing your hands won’t make much difference. It really depends on how sensitive you are to the dog or cat.

(These are the best air purifiers for pets.)

Vacuum weekly

If you have more than one pet or one that sheds more dander, you may have to do this chore a couple of times a week. “People with pet allergies definitely need to clean more frequently,” says Dr. Sullivan.

Use a high-efficiency HEPA filter vacuum. If you don’t have someone who can take over this task, wear a mask to protect against breathing in the allergens that get kicked up when the vacuum is running.

If you can manage to, keep your pets off the furniture and provide dog and cat beds. Carpet-less flooring and washable area rugs are easier don’t trap as many allergens.

Give your dog and cat, yes, you heard that right. You can bathe a cat without getting your eyes scratched out, and it will be worth the effort because it can cut back on airborne allergens.

Tubby time also helps remove pollen. If your dog or cat likes to roll around in the grass, their coat can be covered in the stuff, especially when the pollen count is high. Regular brushing helps too. But do that outside and wear a mask if necessary.

(Should your dog be sleeping in your bed?)

Hypoallergenic pets

Sorry to give you false hope, but there are no truly hypoallergenic dogs or hypoallergenic cats. No dog or cat is 100 percent guaranteed not to cause an allergic reaction. Ever. Not even a hairless Chinese Crested dog or hairless Sphynx cat.

That said, just because you have a cat or dog allergy doesn’t mean you will be allergic to every cat and dog you encounter.

“There are going to be certain breeds of a dog or a cat that you’re going to do a lot better with, but that may be particular just to you,” says Dr. Sullivan.

If you want a pet, plenty of dog and cat breeds fall into the “low-allergen” category. Still, that’s no guarantee their dander won’t affect you.

Besides an allergy test, the best way to know if the cat or dog you want to bring home won’t send you into a sneezing palooza is to interact with it first. Pet the dog or cat (or any other animal) and rub your fact next to theirs.

“If you start sneezing or have itchy eyes or itchy nose, you’re probably not going to want to get that particular animals,” says Dr. Sullivan.

When to treat pet allergy symptoms

Allergies are a bit different than some conditions in terms of treatment. In most scenarios, you take medicine after you get a headache or cold.

Allergies demand a preemptive strike. It’s almost always better to take allergy medicine ahead of exposure to fend off a full-blown allergy attack, whether it’s pet dander, pollen, or other allergens.

Let’s revisit the scenario of visiting a friend with a pet.

“I always recommend pre-treating at least 30 minutes ahead of the exposure,” says Dr. Sindher. That goes for people with allergies plus asthma too.

“I recommend pre-treating with their asthma medications as well. If the situation is avoidable, then the recommendation is definitely to avoid.”

When the symptoms aren’t treated right away, it’s like a raging allergic storm. “Once there is inflammation in the nose it is really hard to get it back down,” adds Dr. Sindher.

So, even if you pop an allergy pill after the fact, it could take hours and repeat doses to feel better.

Pet allergy medicines at the pharmacy

You might be able to get some relief if your symptoms tend to be mild. For the most part, the antihistamines on the shelf are very similar, Dr. Sullivan says. The main difference is the ones that can make you drowsy.

A saline nasal rinse helps flush away allergens, but some people prefer a pill. There are also nasal sprays that are good for controlling the drip and stuffiness.

Decongestants are another option, but use those with caution if you have heart conditions.

“They definitely raise your heart rate and blood pressure, and we don’t want to cause cardiac events over a stuffed up nose,” advises Dr. Sullivan.

Prescriptions and allergy shots

If you have a pet dander allergy, your doctor might prescribe prescription-strength antihistamines to help keep symptoms at bay or take them on an as-needed basis. Often, pet allergies, especially severe cat dander allergies, need something potent.

Allergy shots (immunotherapy) can lead to lasting remission of pet allergy symptoms for some people and may help guard against developing new allergies.

Allergy shots are an option after an allergy test identifies you are allergic to pets. The shots contain tiny doses of allergens and are increased over time. Ideally, you become progressively less sensitive to pet allergens.

It’s important to know the process will take a few months of weekly allergy shots, then possibly a few years of monthly maintenance shots. And they don’t work for everyone.

In Dr. Sindher’s experience, one-third of her patients have remission, one-third experience fewer symptoms, and one-third of the shots don’t work at all.

What about other pets?

We mentioned cats and dogs, but what about all the other cute critters like rabbits, hamsters, gerbils, and such? You can be allergic to them, but the most potent allergens from these animals are saliva and urine.

And where do that saliva and urine end up? In the bedding of their cages. A lot of allergens can be packed into a small space.

To reduce allergens:

  • Don’t hold the animal too close to your face
  • Wash your hands with soap and water after handling
  • Use bedding that is less likely to produce dust that will disperse into the air when the critter moves about
  • Clean the cage a couple of times a week and don gloves and a mask to keep allergens away

Next, check out why it feels good to look into your dog’s eyes.