How long do pet allergy symptoms last after exposure

If you are allergic to dogs or to a specific dog, you can develop a variety of symptoms triggered by dog exposure. A runny nose, coughing, or itchy eyes are among the most common effects of a dog allergy.

You might know that you have a dog allergy based on the course of your reaction. But the situation can be very confusing, particularly if you have frequent contact with dogs.

Regularly bathing the dog may reduce your allergy symptoms, but some people will still have persistent symptoms. You may need to avoid being around dogs or take allergy medication if you can't avoid dog exposure.

How long do pet allergy symptoms last after exposure
How long do pet allergy symptoms last after exposure

Hero Images / Getty Images

Symptoms

A dog allergy can affect children or adults. This type of allergy can trigger a variety of effects, including respiratory symptoms and skin reactions.

You may begin to notice a pattern of symptoms that occurs whenever you spend time with dogs or with a certain dog. Clothes, furniture, carpet, or other materials that a dog came in contact with can trigger allergy symptoms, as well.

Symptoms of a dog allergy usually begin within an hour of exposure. They can last anywhere from a few minutes to long after the pet is gone, since its dander can remain in the air, on the furniture and on your clothing.

Common symptoms of a dog allergy include:

  • Itchy, runny, or stuffy nose
  • Sneezing
  • Red, itchy, or watery eyes
  • Coughing
  • A sore throat
  • Itchy skin
  • A skin rash (it can be anywhere on your skin, not just on the area of direct contact)

Asthma can be exacerbated by dog allergies. You or your child may have an asthma attack, characterized by wheezing and shortness of breath when exposed to dogs.

In rare instances, a person can experience anaphylaxis—a severe allergic reaction, characterized by throat swelling and trouble breathing. This is an emergency that requires urgent medical attention.

Dog-Induced Symptoms Unrelated to Allergies

Keep in mind that a dog allergy should not cause fevers, skin wounds, or blisters. Dogs can transmit other illnesses to humans that cause effects different from those of allergies.

Some people experience severe anxiety when around dogs—this is a phobia and not an allergic reaction.

Causes

Your allergy can be triggered by dog fur, saliva, urine, feces, or dander. Pet dander is very small material shed by pets, and it is composed of dead skin cells. Dander may lodge in fabric, triggering an allergic reaction even when the pet is not in the same room.

A person can be allergic to all dogs or to certain dog breeds. While some breeds of dogs are marketed as being hypoallergenic, there is no evidence to support this claim. In fact, researchers found that the amount of allergens in homes with supposedly hypoallergenic dogs was no different from homes with dogs that are generally considered to be non-hypoallergenic. Anecdotally, dogs with certain characteristics--non-shedding coats, short hair, small size--are reported to be less allergenic. But there is no way to be sure you won't be allergic to a particular dog other than to spend plenty of one-on-one time with the animal before buying or adopting it.

Immune Reaction

A dog allergy occurs due to dog allergens that induce an allergic reaction. An allergen is a harmless substance that triggers the body's immune system to react harmfully.

With a dog allergy, one or more dog allergens trigger reactions by allergy cells like mast cells and basophils using an antibody called immunoglobulin E (IgE).

This is a temporary reaction, lasting between a few minutes to a few hours. But recurrent or constant exposure to the allergens can make the reaction last longer.

Diagnosis

It can be very difficult to self-diagnose a dog allergy. Dog allergies are less common than cat allergies.

If you notice that your symptoms begin during or after exposure to a dog, be sure to talk to your healthcare provider. You may need to have a blood test to measure your IgE levels, or a skin prick test to check your reaction to dog allergens.

What Types of Allergy Tests Are Available?

There are a number of other health issues that you can develop due to dog exposure, and the management of these health issues differs from the management of dog allergies.

Conditions you can get from dogs include:

  • Poison ivy: This is a rash caused by a hypersensitive reaction to the poison ivy plant. This rash is triggered by touching the plant or coming into contact with oil from the surface of the plant. Poison ivy causes an itchy, red, blistery rash that can develop anywhere on your body (including the eyes). While it is rare for dogs to react to poison ivy like humans do, you can get this rash by coming into contact with the plant's oils on your dog's skin or coat.
  • Fleas: Dogs can have fleas and may transmit them to humans. Fleas are tiny insects that can bite your skin, especially under your hair. They can cause itching and red spots on your skin.
  • Gastrointestinal (GI) infections: There are a number of GI infections that you can catch from coming into contact with a dog's feces. If the infectious microorganism (usually a bacteria, virus, or parasite) gets into your mouth, you can become very sick. These infections can cause stomach aches, vomiting, diarrhea, muscle aches, and fevers. Giardia, salmonella, and cryptosporidium are examples of infections you can catch from a dog.

Treatment

Depending on the severity of your allergy, you may be able to make a few adjustments that can prevent and alleviate your symptoms. Strategies that can help prevent your symptoms include keeping your dog clean, vacuuming dog hair, and making sure that there is no dog urine and feces inside your home. However, these precautions may be impractical. For example, if you need to bathe your dog every day, this can be excessive for both you and your dog.

In some instances, taking allergy medications or getting allergy shots on a regular basis can help prevent your symptoms.

Despite all the best precautions, some people have severe allergies and absolutely cannot be around dogs. It may take some time for you and your healthcare provider to assess the approach that works best for you.

If you cannot live with your dog anymore or if you have moved into a home that is triggering your dog allergy, you may need to change the carpet, drapes, and other fabrics to better eliminate the allergens from your environment.

Treatment of Dog-Induced Infections

If you develop an infection due to dog exposure, you and your dog will need to be treated with antibiotics or anti-parasitic treatment. Be sure to take your dog to a veterinarian and to see a healthcare provider for your infection too.

Keep in mind that the medications and doses for you and your dog will be different.

A Word From Verywell

Despite these allergic reactions, dogs are more likely to be good for your health than to cause problems. Some experts suggest that young children who live with dogs are less likely to develop allergies later in life. Dogs can also help a person with vision problems and some dogs can be trained to help people who have epilepsy.

While dog allergies are not common, the effects can be distressing. If you are allergic to a dog, it is important that you take care of your health, even if that means parting from a beloved dog.

How long do allergic reactions to pets last?

Pet allergy symptoms will last until the animal is permanently removed from the home. However, many symptoms can last for months afterward as pet dander and fur can stay in a home for months and even years later. Often, carpets hold animal dander and fur much longer.

How long do pet allergies take to show up?

How long after being around pets do symptoms appear? It depends on the severity of your pet allergies. If you have severe pet allergies, symptoms may appear within 15-30 minutes of encountering a pet. If you have mild pet allergies, symptoms may appear a few hours to a few days after encountering a pet.

How long do cat allergy symptoms last after exposure?

Once the allergen is removed, symptoms usually settle within a few hours but can last for 2-3 days, for example if there has been significant eye swelling, the use of antihistamines and on some occasions even oral steroids can help this settle more rapidly.