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.
Image used with permission by copyright holder

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. 

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…
Does your dog like to lean on you? Here’s why
The sweet reason your dog likes to lean on you (and when to be concerned)
Dog leaning on human in blue sweater

Our attitude toward dogs has shifted significantly in modern times, with humans considering their pets more like family members that they love just as much (or more) than their two-legged relatives. However, we have long been partners with canines, which have helped us hunt for food and protected us with our lives. This long-running partnership comes even though we don't speak the same language.

Therefore, you may wonder what is going on in your dog's head when they display certain behaviors. For instance, you may ask, "Why does my dog lean on me?" The answer is generally straightforward and sweet. However, a dog leaning on you may be a cause for concern, too.
Why does my dog lean on me?

Read more
How to get your dog to stop hiccuping
You can help your dog get over hiccups
A close-up shot of a Shiba Inu sitting on a sofa.

Most of us have suffered from a bout of the hiccups at least once, and while hiccuping can be annoying, it's very rarely harmful. However, in some cases, hiccups can be a symptom of an underlying medical problem, such as pneumonia or pancreatitis. In very rare cases, hepatitis or liver cancer may cause hiccups.

This sounds scary, but does that mean you should be worried if your dog has hiccups? More often than not, your dog's hiccups will resolve within a few hours, but if your pooch has difficulty eating, drinking, or sleeping because of his hiccups, it's a good idea to take him to the vet. Here's what you'll want to know about canine hiccups.
What causes hiccups in dogs?

Read more
Do mosquitoes bite dogs? How to protect your pet this summer
What you'll want to know about dogs and mosquito bites
A brown puppy scratching behind the ear

Your dog will only be on Earth for a fraction of the time you'll be here, so it's important to take advantage of every moment of sunshine you have together. Whether you're vegging on the patio chair or hiking somewhere new, having your pooch by your side makes summertime so much more magical.
But there are a few details about the warmer months that aren't so nice, especially the bugs. Mosquitos are particularly annoying on those perfect summertime evenings, but do they bug your dog as much as they bug you? Do mosquitoes bite dogs? Are mosquitos dangerous to dogs? There are so many questions to ask!

Do mosquitoes bite dogs?

Read more