Dog allergySophie Matzik is a freelance writer for the NetDoktor medical editorial team.
Dog allergy is a hypersensitivity of the immune system to certain substances secreted by dogs in saliva, urine and glandular secretions. Dog allergy is manifested by symptoms such as red eyes, sneezing and a runny nose. Depending on the severity of symptoms, a dog allergy is treated differently. Read everything important about dog allergy here.
Symptoms: Sneezing, coughing, skin rash
Treatment: Medication to relieve symptoms, hyposensitization
Causes and risk factors: Certain proteins released by dogs (allergens) meet hypersensitive immune system
Diagnostics: Prick test, blood test
Course and prognosis: Good if affected people avoid contact with dogs, in severe cases, an asthma disease develops as a result of the allergy
Prevention: Avoid contact with dogs and their owners
What is a dog allergy?
The dog allergy is a hypersensitivity to certain, actually harmless proteins that are emitted by dogs. These proteins are found in saliva, urine, skin and sebaceous glands. Thus, they are found on the dog's dander and hair. If the allergens get into the respiratory tract and onto the mucous membranes of humans, they cause an allergic reaction in some people.
Colloquially is often called a "dog hair allergy" the speech. But this term is misleading. It is not the dog hairs themselves that trigger an allergy, but the particles that stick to them.
Dog allergy is the second most common allergy to animal dander after cat allergy. All dogs produce allergens. There is no breed of dog to which this does not apply, although there are always rumors about it. In contrast to a cat allergy, in which those affected are usually allergic to all types of cats, a dog allergy sometimes exists only to individual breeds. For example, more people are allergic to boxers than to poodles.
A few people with dog allergy also show signs of allergy on contact with cats. Dog and cat basically produce different proteins. However, some of them are similar in their basic structure. It is much more common for people allergic to cats to develop allergic symptoms on contact with dogs. This phenomenon is called cross allergy.
Learn more about cat allergy here.
How does a dog allergy manifest itself?
In case of dog allergy, the symptoms appear directly after contact with the allergens. The dog hair allergy is an allergy of immediate type. This means that symptoms appear immediately after contact with the allergen in dog hair allergy. No direct contact with dogs is necessary to trigger allergic symptoms. Dog allergens also transfer through the air, objects or other people.
Symptoms of dog allergy depend on where contact with the allergens happens. If they get into the eyes of an allergy sufferer, red, burning or itchy eyes develop up to conjunctivitis. If they are inhaled and enter the nose, for example, the symptoms are reminiscent of hay fever. Increased secretion production, swelling of the mucous membranes. There is often a persistent sneezing irritation.
The mucous membranes in the throat also swell up. This results in coughing, difficulty swallowing and scratching of the throat. Redness or swelling appears on the skin in some allergy sufferers.
Compared to those of a cat allergy, the symptoms of dog allergy are often less severe. If an allergy remains untreated for a long time, there is a risk that the symptoms will worsen over time. In rare cases – especially if a dog allergy is not treated for a long time or in case of very high allergen exposure – there is a risk of asthma attacks with breathing difficulties and respiratory distress or even anaphylactic shock.
What can you do against a dog allergy?
In dog allergies, the symptoms are generally less pronounced than in other allergies. In many cases, it is therefore sufficient for treatment to avoid particular risk factors. In the case of dog allergy, the first priority is to avoid any contact with dogs. In the case of a severe dog allergy, a dog living in the household must be given up.
Dog owners who have developed dog allergies in the course of their lives often find it difficult to part with their pet. If the dog allergy is only slightly pronounced, this is also not absolutely necessary. But it is important to reduce the contact with the dog. Allergy sufferers better avoid having their dog lick their face, don't let it sit on their lap, and wash their hands thoroughly after every contact.
Various medications such as antihistamines or cortisone preparations are used if necessary. These dog allergy tablets relieve symptoms, but do not eliminate the cause. Some allergy sufferers take it as a preventive measure, such as when a dog owner is scheduled to visit them.
If the dog allergy is accompanied by a significant restriction of the quality of life or there are very severe symptoms, hyposensitization is also a possibility. The allergen to which the body reacts is directly administered in increasing doses over a period of several years. It is either injected under the skin (subcutaneous) or dripped under the tongue (sublingual).
The effect is most easily explained by the principle of habituation: By administering higher and higher doses, the body tolerates larger amounts of the allergen and no longer reacts with symptoms to lower doses. If symptoms reappear in the course of life after hyposensitization, it is possible to repeat the treatment.
How does a dog allergy occur??
The cause of a dog allergy are certain proteins, so-called allergens, which are released by dogs with their saliva, urine and through skin glands. These proteins stick to the dog's dander and hair. From there, they are either released into the air, onto objects, or immediately to humans through direct contact.
The dog allergens are actually harmless substances. The real cause of dog allergy is an overreaction of the immune system. If the immune system comes into contact with the substances for the first time, there are no symptoms of allergy yet. However, the immune system recognizes the substances as foreign to the body and classifies them as harmful. Therefore it forms antibodies against them.
When the dog comes into contact with the allergens again, the antibodies are activated. These now stimulate cells in the body, which, among other things, release histamine. Histamine triggers a swelling of the mucous membranes, an increased production of mucus and a widening of the blood vessels in the body.
To develop symptoms of dog allergy, sufferers don't even have to have direct contact with dogs. The allergens are transmitted through the air and by pet owners who wear the dog hairs and dander on their clothing. High concentrations of allergens can therefore also be found in public places such as schools or public transport. Dog allergy occurs in some cases even in people who have never had personal contact with a dog.
How is a dog allergy diagnosed?
If a dog allergy is suspected, the family doctor or an allergist is the right contact person. In a first conversation, this person takes the medical history (anamnesis). Patients describe the symptoms in detail. To narrow down the nature of the symptoms and possible causes, the doctor may ask questions such as:
– If the symptoms occur mainly indoors or also outdoors? – Do you have permanent complaints or rather episodic? – Do you have pets? – Were there people in your family with similar symptoms?
Because of the large number of possible causes of allergy and also because the symptoms often point to other diseases, the diagnosis of allergy is sometimes difficult. After the initial interview, a physical examination takes place. Among other things, the skin, eyes and respiratory tract are examined. The lungs are listened to. The general state of health is checked.
The doctor may ask the patient to come back a second time and keep an allergy diary in the meantime. You enter the following in an allergy diary:
– When and where the discomfort occurred – What you were doing – What you ate and drank that day – What medications you took – What conceivable causes would be
If the doctor has made a tentative diagnosis, he will perform an allergy test. Today, the so-called prick test is usually used as an allergy test. Possible allergens are dripped onto the skin, usually on the forearm, and the skin underneath is lightly scratched. If a dog allergy exists, the skin under the corresponding allergen will redden, swell and possibly form pustules within 15 to 20 minutes. If there is no allergy, the prick test shows little or no skin changes.
In addition, some patients undergo a special blood test, a so-called RAST test. The blood is tested for antibodies that indicate an allergy. A normal blood count can also be used to rule out inflammations and infections of the body that are associated with symptoms similar to a dog allergy.
Finally, if the findings are uncertain, a provocation test is performed. The suspected allergen is applied directly to the nasal mucous membranes. The provocation test is rarely used today, as it can cause very severe allergic reactions in extreme cases. After the test, follow-up of at least half an hour is also necessary.
How does a dog allergy proceed??
Disease progression and prognosis of dog dander allergy depend primarily on the behavior of the affected individual. If the cause of the allergy, i.e. contact with dogs, is consistently avoided and the patient refrains from owning dogs, the symptoms are usually significantly reduced. If exposure persists, symptoms threaten to worsen with age. In extreme cases, a dog allergy develops into bronchial asthma with permanent symptoms.
After a Hyposensibilisierung usually a favorable prognosis exists. If allergy triggers are avoided in the future, dog allergy sufferers have a good chance of living a symptom-free life.