Skip to main content

PawTracks may earn a commission when you buy through links on our site.

Is your dog having an allergic reaction? Watch out for these warning signs

Pollen, chemical fumes, insect bites, and certain types of food are all common allergens in humans. Symptoms range from mild annoyances, such as itchy, watery eyes, to life-threatening anaphylaxis. For the most part, it’s easy to tell when a fellow human is suffering from an allergic reaction. But what about a dog’s allergic reaction? They might not be as immediately recognizable as your seasonal allergies, but there are signs to keep an eye out for if you suspect your dog has allergies. We’ll tell you what to look for, what you can do to help, and give you a general idea of how long your precious pooch will have to deal with the symptoms of an allergic reaction. 

A Fila Brasileiro sneezing in the woods.
olgagorovenko / Shutterstock

How can I tell if my dog is having an allergic reaction? 

Just like you, it’s possible for your dog to suffer from unique allergies. For brevity’s sake, we’ll cover the four most common causes of allergic reactions in dogs. 

Recommended Videos

Acute allergic reactions

Unlike a chronic allergic condition, an acute allergy is a sudden response to an irritant, such as a sting or bite from an insect. There are other causes of acute allergies in dogs, but stings and bites are the most common. Swelling, itching, and vomiting are common, but dogs suffering from anaphylactic shock could experience difficulty breathing, show signs of cyanosis – a bluish tint to the lips and gums caused by the lack of proper blood oxygenation – and might even lose consciousness. 

Food allergies

Yet another common allergy dogs suffer from, a food allergy often causes stomach upset like nausea, vomiting, and diarrhea. That being said, some dogs might develop skin conditions, begin to show signs of brittle fur, or might even suffer from the loss of fur. If your pup begins scratching at himself while suffering from gastrointestinal issues, it’s very possible he’s allergic to something in his kibble. To determine the allergen, your dog’s vet might recommend an elimination diet, or he may prescribe a formula developed for dogs with food sensitivities, such as this one from Hill’s Prescription Diet.

Seasonal allergies

Some people are overjoyed when spring rolls around each year. Others dread the sudden flare-up of seasonal allergies. And your dog might concur! Just like people, dogs can suffer from seasonal allergies with similar symptoms, such as puffy, watery eyes, itchy skin, ear infections, a running nose, and sneezing fits. While you should speak with your vet to make sure your dog’s condition is related to seasonal allergies, if you notice him sneezing at the same time every year, that’s likely the case. 

Skin allergies

Just like some people have sensitive skin, so do some dogs. Whether your pooch has been exposed to an irritant from fleas, ticks, plants, chemicals, or even the detergent you use to wash your linens, skin allergies are miserable. Look for symptoms like hives, dry and flaky skin, redness of the skin, and itching. Make sure your precious pooch is on a flea and tick preventative, take precautions when growing certain types of plants and flowers, and use a gentle, fragrance-free detergent to wash any fabrics your dog comes into contact with. 

A Jack Russell Terrier biting an itch on his hind leg.
Yuliya Evstratenko/Shutterstock

What can I give my dog for an allergic reaction? 

When it comes to treating your dog’s allergies, look no further than your own medicine cabinet. Benadryl, a common antihistamine used to treat allergies, works as effectively in dogs as it does in humans. Thanks to the main ingredient, diphenhydramine HCI, Benadryl combats the symptoms of allergies with minimal side effects. Unfortunately, the FDA has yet to approve Benadryl for veterinary use, but vets frequently recommend the use of Benadryl in treating dogs and cats with allergies. Make sure to administer the correct dosage for your dog’s weight, and speak to your vet before giving Benadryl if your pup is pregnant or suffers from hypertension, seizures, hypothyroidism, cardiovascular disease, glaucoma, or allergic lung disease. 

How long will my dog’s allergic reaction last?

As much as we want to give you a cut-and-dried answer, the truth is… well, it depends on the allergen and the severity of your dog’s reaction. If your dog is suffering from a skin allergy, you can look for the redness and irritation to last somewhere between two and three weeks. If your pup has seasonal allergies, you can expect to see symptoms for as long as the allergen is in bloom. Allergic hives generally appear within minutes of exposure to an allergen, and they can fade just as quickly. However, hives can also last up to 48 hours, so don’t be overly concerned if they don’t clear up right away. 

A black Schnauzer puppy scratching an itch.
Image used with permission by copyright holder

Final thoughts on allergies

Allergies are as uncomfortable for dogs as they are for us. Whether your pup is suffering from an insect sting, a skin reaction, seasonal allergies, or a food allergy, we recommend taking your pup to the vet for a thorough checkup. Antihistamines can help manage symptoms, but your vet might also prescribe oral, injectable, or topical steroids to help control your dog’s allergic reaction. Lastly, if your dog experiences difficulty breathing, you should take him to the emergency vet right away. 

Mary Johnson
Contributor
Mary Johnson is a writer and photographer from New Orleans, Louisiana. Her work has been published in PawTracks and…
Why does your dog stick out their tongue? Vets explain the ‘blep’
This behavior may be cute, but what does it really mean?
A German shepherd puppy sticks out their tongue

There's nothing funnier than a "blep," but what does it mean? Whether you first heard the word blep on the internet (it is meme-worthy, after all), or are learning of it right now, you're in for a treat. Bleps are positively adorable. The term started gaining traction in the late 2010s, though it's no less popular today. The common canine behavior it's based on, however, is a habit as old as time: sticking out a tongue. Yep, a dog's tongue sticking out is enough to break the internet!

It's pretty dang cute, after all, but not always easy to figure out why a dog's tongue is out. Don't worry, though, pet parents — this is a great place to start. Here is everything you need to know about bleps and what they mean.
What is a blep? How about a mlem?

Read more
Why you shouldn’t feed your dog trail mix: The hidden dangers
Here's exactly why dogs can't eat trail mix or their common ingredients
Pug licks their lips and looks into the camera

At first glance, trail mix might look like a healthy snack for everyone in your home. It has a little sugar, some healthy fats, and a small number of carbohydrates to keep you going throughout the day. Sounds great, right?
Although people can eat as much trail mix as they please, the same isn't true for our canine friends. There are many ingredients in this popular combo that aren't safe for dogs to eat. Let's go over a few of the reasons why as we answer some of the most common questions:

Can dogs eat raisins?
Why can't dogs eat trail mix?
Which nuts are safe for dogs to eat?

Read more
Xylitol and dogs: 10 unexpected products that contain this toxic ingredient
Products that hide xylitol and can be toxic to dogs
A Labrador retriever lies on the wooden floor next to a food bowl

Chocolate, grapes, table scraps: There are some foods every pet parent knows you shouldn't give to dogs, no matter how cute their puppy-dog eyes are. Unfortunately, many other foods contain several hidden ingredients that can be harmful to our furry friends. Take xylitol, for instance. You might not know exactly what it is, but it certainly sounds more like a musical instrument than an ingredient.

While it is perfectly fine for humans to ingest this sugar substitute, xylitol and dogs are another story. If you have questions, don't worry! We'll help you learn:

Read more