Allergy – Causes, Symptoms & Treatment


One speaks of an allergy when the body’s immune system reacts extremely strongly to certain substances and environmental influences. This is also referred to as an overreaction. Typical allergies are hay fever , house dust allergy and sun allergy . The signs of most allergies are usually clearly visible. A runny nose , watery eyes , swelling , itching and shortness of breath are not uncommon and should be examined by a doctor.

What are allergies?

Basically, an allergy is nothing more than the result of an overzealous immune system. The immune system usually serves to fight off pathogens and pests in order to protect the body.

In some people, however, even harmless intruders, such as food components or pollen, are classified as harmful, causing the body to react allergically to the foreign intruders.

However, an allergy can not only exist against pollen or certain foods, house dust, components of cosmetics, animal hair or other things that you come into contact with in everyday life can also lead to a hypersensitivity reaction. Since there are many triggers for an allergy, both children and the elderly can be affected.


Why some people develop an allergy has not yet been fully clarified, because there are many causes that can trigger allergic reactions. Basically, the immune system considers an actually harmless foreign body to be harmful and fights it off, so that the body reacts with skin irritation , watery eyes and similar symptoms.

There are many reasons why some people are hypersensitive. For example, the tendency towards an allergy can be inherited via the genes. If you have several allergy sufferers in your family, you will probably also react more sensitively to certain substances.

The fact that allergies occur much more frequently in industrialized countries than in other countries also suggests that the body needs a certain amount of dirt and germs to develop its defenses. If you place too much value on hygiene and keep your home rather sterile, you are rarely protected against pollutants from the environment, which you cannot avoid, however.

For this reason, small children and babies should not be cleaned too sterile. However, they should also not come into contact with dirt and vermin. The healthy mediocrity is still the most natural way to prevent later allergies.

Symptoms, Ailments & Signs

Allergy can be accompanied by visible as well as hidden symptoms and signs. The most common and well-known signs are reddened and very itchy areas of skin , which can also be swollen. These often arise from direct contact allergies and occur exactly where the allergen comes into contact with the body.

If the itching becomes too severe, many sufferers scratch themselves until open skin and wounds appear. Also typical symptoms of allergies are irritated and swollen mucous membranes, for example in the area of ​​the eyes, mouth and throat.

However, allergies can also make themselves felt through severe shortness of breath , especially when the allergenic substance has been inhaled or eaten. Symptoms such as dizziness , tachycardia and rapidly increasing blood pressure can also indicate an allergy and the onset of anaphylactic shock.

Especially in connection with food allergies and food intolerance, the gastrointestinal tract can also be affected by the symptoms caused by the allergy. Digestive problems can occur to a greater or lesser extent, ranging from nausea and vomiting to mild or even very severe diarrhea.

Circulatory problems are usually the result. If the allergic reaction is milder, the reactions of the digestive system can also occur with a delay of up to 24 hours.


The course of an allergy depends primarily on which allergens the person is hypersensitive to. The eyes, which react with redness and itching , are often affected . Conjunctivitis and heavy tear production are also not uncommon with an allergy. In addition, swelling of the conjunctiva and eyelids often occurs.

However, allergic reactions can also affect the bronchi. Unlike eye reactions, these effects can also cause permanent damage and are therefore classified as more dangerous. In the case of hypersensitivity, the bronchi constrict while at the same time too much bronchial secretion is produced, causing inflammation. As a result, the bronchial mucosa can be damaged.

An allergy can also lead to breathing problems if the nose is affected. The nasal mucous membranes swell while at the same time too much secretion is produced. The result of an allergy is severe itching, increased sneezing and, in the worst case , inflammation of the sinuses .


An allergy leads to a characteristic symptomatology, which leads to corresponding complications. First of all, sensitization can occur to almost any substance, so that it is almost impossible to be allergic to anything. In the case of frequent contact with the allergen, this can lead to serious impairments in the quality of life.

In some cases, an allergen can trigger Quincke’s edema . This causes swelling, especially in the deeper layers of the skin, which is more serious. It mainly comes to swelling of the genitals, hands, feet and face. In the face, this can lead to severe swelling in the airways, which can lead to severe shortness of breath and the impending fear of suffocation.

It also narrows the esophagus, which can make it difficult to swallow. In the worst cases, an allergic reaction results in anaphylactic shock . This leads to a sharp drop in blood pressure in the affected person and important organs are no longer supplied with enough blood, which can cause them to die and lose their function.

This condition is life-threatening and should be monitored by emergency medical personnel. Furthermore, so-called cross-reactions can occur, in which substances that appear molecularly similar to the allergen can also trigger an allergic reaction and cause the same complications as the original allergen.

When should you go to the doctor?

Allergies have mild and severe courses, but regardless of the severity of the first symptoms, a medical diagnosis is important. Conspicuous swelling and redness, hives on the skin, watery eyes and shortness of breath in severe allergic reactions are typical of an allergy and should be examined. In the case of some allergies, the cause of the person affected is obvious, because the presumed allergic reaction always occurs in the same situation – for example when eating nuts or other foods.

In this case, at the first visit to the doctor, the patient should express the suspicion of what an allergy exists to. However, a doctor’s visit is also useful if allergic symptoms occur without a clearly identifiable cause, because then it could be pollen or other environmental influences in the air we breathe. Allergy sufferers with a known diagnosis should pay attention to the severity of their symptoms.

If they become more severe and this is not a one-time exception, those affected should arrange another doctor’s appointment. Allergies can worsen – in this case, the patient should know what to do in case of a severe allergic reaction. It is also important to visit the doctor again if someone who is allergic has a reaction to a substance that has not previously caused any problems. New allergies can also occur and should be recognized in good time.

Treatment & Therapy

A real cure for all allergies is not yet possible. In many cases, however, it is sufficient if the person concerned avoids the respective allergen so that he does not react to it.

However, if this is not possible, further measures must be taken depending on the severity of the allergy. For example, there are medications that can alleviate the symptoms. However, aids such as special filters or bed linen suitable for allergy sufferers can also be useful.

In some cases, sensitization to the allergy-triggering substances can also lead to the symptoms becoming significantly weaker.

Outlook & Forecast

An allergy can significantly restrict the life and everyday life of the patient. The patients suffer from severe shortness of breath and usually also from a runny nose. Furthermore, it often leads to watery eyes and itching, which can occur all over the body. In some cases there is even diarrhea or vomiting . An increased heart rate can also occur.

The severity of the symptoms is different for each person, so that in the case of an allergy it is usually not possible to predict the general course of the disease. However, the patient’s quality of life is significantly reduced by the allergy. Special complications or even life-threatening conditions usually only occur if the person concerned is exposed to the allergy triggers over a longer period of time.

The life expectancy of the patient can also be reduced. The symptoms can be relieved with medication. The patient must also avoid the allergens so that the symptoms do not appear in the first place.


It cannot generally be predicted whether the person affected will have follow-up care options in the event of an allergy. As a rule, these possibilities depend very much on the exact characteristics and type of allergy, so that no general prediction can be made here. However, the options are usually limited.

In the case of an allergy, those affected should primarily avoid the triggering substance in order to alleviate the symptoms. Strenuous activities that strain and overtax the body should also be avoided. In some cases, the allergy can also be treated with medication, so it is important to take these medications regularly.

Possible interactions should also be discussed with a doctor. In most cases, the life expectancy of the patient is not negatively affected by an allergy. However, if a shock or a severe seizure should occur, the hospital can be visited directly or an ambulance can be called. Those affected may have to change their habits or diet in order to avoid the substances that trigger the allergy. This is the only way to avoid further complications.

You can do that yourself

Pollen typically flies during a certain time of year. However, the exact timing of the pollen count not only depends on the type of plant, but also on the weather. The pollen count forecast on the radio or television therefore provides up-to-date information. Anyone who suffers from hay fever should spend little time outdoors during the critical phase. In addition, it makes sense to avoid outdoor activities that are physically demanding.

food allergy necessitates a thorough reading of the ingredient list on packaged foods. In Germany, selected allergens can be read on the list of ingredients even if they could only be found in traces in the product. This includes, for example, peanuts in food. Allergy sufferers abroad must find out whether a corresponding labeling is also carried out there.

Self-help groups for allergy sufferers are often aimed at people who have to accept severe limitations in their lives or who suffer greatly from their allergies for other reasons. Those affected exchange experiences in such a group and experience understanding and support from other members.

Allergy sufferers should not deliberately expose themselves to the substance to which they are allergic. There may be a risk of allergic shock or another serious reaction. When it comes to possible treatment, allergy sufferers should always follow the advice of an experienced doctor and not try it on their own.

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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.