Can You Develop a Cat Allergy Later in Life? Here's What You Should Know

18 juil. 2025

Written by: Pacagen Team
Reviewed by: Evan Zhao, PhD
Evan is a bioengineer, a loving dad to Miao Miao, and the founder and CEO of Pacagen.

You’ve loved cats for years, maybe you’ve even lived with one (or five). But now? Suddenly, your nose won’t stop running, your eyes are red and itchy, and you’re sneezing! You're left wondering,“Can you develop a cat allergy later in life?” The answer might surprise you.

Yes, you can suddenly become allergic to cats - even if you were never before!

It’s a common misconception that allergies only develop in childhood. In reality, your immune system is always evolving. So if you’ve been asking Google things like “can you develop a cat allergy later in life?” or “can you suddenly become allergic to cats?” - join the club. So many people are surprised when it happens.

can you develop a cat allergy

Let’s break it down: what exactly is a cat allergy?

Spoiler: A cat allergy doesn’t mean you’re allergic to the cat itself. It is usually a reaction to a protein called Fel d 1, which is found in saliva, skin flakes (aka dander), and sometimes even their pee. Delightful, right?

These little proteins float around in the air or cling to your couch, clothes, rugs - you name it. When your immune system starts to freak out over these harmless particles, that’s when the allergy symptoms kick in. We are talking about things like:

Sneezing that won’t quit
Runny or stuffy nose
Itchy, watery eyes
Coughing or wheezing
Skin rashes or hives

And if you’ve got asthma? Cat allergies can definitely make that worse.

But... why now?

Yeah, it’s super confusing. Like, can you become allergic to cats even after living with them for years without a problem? Apparently, yes. Here's why it might be happening:

Changes in your immune system: You might have gone through major life events like pregnancy, illness, or significant stress, and now your immune system just reacts differently to allergens.
Increased exposure: Maybe you are around cats more. Maybe you adopted one or moved in with someone who has three. More exposure = more chances for your body to develop sensitivity.
Environmental shifts: Moved to a new city? New climate? Changes in air quality can make your body more reactive to allergens.
Allergy threshold overload: If you're already sensitive to other allergens like pollen or dust, your system can get overwhelmed and go, “Cool, now I’m allergic to cats too.”

So yes, you can develop allergies to cats later in life, and it might not be clear why it’s happening... but you're not imagining it.

Adults get allergies too - it’s not just the kids

Many people ask, “Can adults develop cat allergies, or is it just a kid thing?”

While kids are more likely to develop allergies early on, adults can absolutely experience developing cat allergies later in life.

Adults in their 30s, 40s, 50s - even older - can start developing allergies. You might’ve been totally fine your whole life and then boom: you wake up one day and your cat cuddles now come with a side of tissues.

How do you know if it’s a cat allergy?

Here’s what to look out for:

Do you feel worse after being around cats?
Do your symptoms chill out when you leave a house with cats?
Have you been rubbing your eyes non-stop after a cuddle session?

If the timing seems suspicious, it’s worth investigating. Here’s what you can try:

Track your symptoms: Do you feel worse when you’re near a cat? Better when you're away? Patterns help.
See an allergist: skin tests or blood tests can confirm if cats are the culprit.
Try temporary avoidance: I know, this one's the hardest, but stay away from cats temporarily and see if symptoms improve.

What can you do if you develop a cat allergy?

First, don’t panic. And don’t assume you have to give up your cat, either. That’s a last resort - not your only option.

Here’s what helps:

Clean often: Vacuum with a HEPA filter, wash bedding frequently, and dust surfaces to reduce dander buildup.
Use air purifiers: HEPA air purifiers can help trap airborne allergens.
Keep cats out of the bedroom: Create an allergen-free zone to let your immune system relax at night.
Bathe your cat (carefully): Regular bathing or wiping them down gently (with vet approval) can reduce allergens in fur.
Talk to your doctor: Allergy meds, antihistamines, or even allergy shots (immunotherapy) can help you live comfortably with a cat.
Allergen Neutralizing Sprays and Food Toppers: Pacagen’s cat allergen neutralizing spray binds with the cat allergens in the environment and on surfaces and neutralizes them upon contact. The food topper helps reduce the allergens in the cat’s saliva, and therefore there is less allergen spread during grooming.

Still scratching your head?

If you're still asking, “Can you develop cat allergies?” or “Why is this happening now?” - you're not alone. Allergy development isn’t always predictable, it’s random and it’s weird, but it is manageable with the right knowledge and daily habits.

And here's the good news: many people with mild to moderate allergies keep living the dream life. With a little extra care and some smart strategies, you likely can too.

Still curious about cat allergies?

Read: Understanding Fel d 1: The Major Cat Allergen
Explore: Top Air Purifiers for Cat Owners
Check out: Everyday Habits That Help You Manage Allergie s

Whether you’re figuring out your symptoms or trying to make life with your cat more comfortable, we've got you covered. Stick around, explore more, and get the info you need to feel better and keep your bond with your feline friend strong.