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Allergy manifestation
Last reviewed: 04.07.2025

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Manifestation of allergy is a whole symptomatic complex, diverse and multifaceted, each manifestation of allergy directly depends on its type, on the provoking factor and on the health of the person himself. Since allergy is a hypersensitivity of the body, any allergen can trigger reactions that, on the one hand, are united by common signs, on the other hand, each person is individual, and therefore reacts to the invasion of the antigen in a specific way.
Typical manifestations of allergies
Some of the most typical allergic reactions are:
- Rash on the skin, of various locations and structures;
- Pain in the eyes, swelling of the eyes;
- Redness of the sclera of the eyes;
- Runny nose not associated with colds;
- Hives;
- Frequent sneezing not associated with colds;
- Hyperemia of the skin;
- Shortness of breath, suffocation;
- Anaphylaxis.
Since ancient times, mankind has known what an allergy is. Actually, the name "allergy" was introduced relatively recently, at the beginning of the last century. A pediatrician noticed a recurring tendency towards atypical reactions to common diseases. Von Pirquet was the first to define the terminology of the disease and described it in some detail. Although many centuries earlier, both Hippocrates and Galen also described in their works the unusual reaction of patients to food, flowering plants and trees, and smells. Since then, every century new theories and versions of the main cause of allergies have appeared, but the medical world has not yet come to a consensus.
The manifestations of allergies depend on which substance of the body takes the first attack of the allergen and how it reacts to the allergen. The first type of reaction - hypersensitivity reaction is explained by the active response of immunoglobulin IgE. Immunoglobulin provokes sensitization (recognition) of the allergen by the body and the consolidation of this property. Such a process, caused by hypersensitivity of the first type, can lead to consequences that are called benign, that is, curable. This is allergic rhinitis, itching, rash. However, there are other reactions that are extremely dangerous not only for health, but also for the life of the patient. These are Quincke's edema and anaphylaxis.
Allergy symptoms are most often caused by visible reasons:
- Flowering (seasonal) of plants, trees;
- Food allergen;
- Intoxication with infectious, bacterial diseases, inflammatory processes;
- Household, industrial dust;
- Air pollution by chemicals;
- Hereditary factor.
The hygiene hypothesis is considered to be a common factor in recent times – a theory of hygiene, which is based on the hypothesis of weakened immunity. Excessive destruction of microbes in the human environment has led to the immune system forgetting how to fight the invasion of harmful agents. There is also no constant load that would train the protective functions. Striving to perform a genetically determined function, the immune system begins to react to any invading factor, regardless of the degree of its harmfulness. The authors of the theory cite many examples of absolutely healthy children and adults in terms of allergies, sometimes living in appalling unsanitary conditions, as one of the arguments. Of course, these people are susceptible to other diseases, but they do not know what an allergy is. Also, a child in a large family is less likely to suffer from allergies than an only child, from whom, literally, dust is blown off. In addition to the "hygienic" theory, unfavorable environmental conditions, unreasonable nutrition, stress can be noted among the reasons. The manifestation of allergies, what does it depend on?
The types of hypersensitivity and their visible signs depend on the types of immune response.
- The immune response phase can be acute. Plasmocytes begin to intensively secrete immunoglobulin IgE, which in turn binds to Fc receptors. The sensitization process begins with the synthesis of secreted IgE and Fc. Repeated invasion of the allergen occurs on already prepared, habitual soil for the antigen. Granules of cells that have already participated in sensitization secrete histamine and other inflammatory mediators (leukotrienes, prostaglandins, cytoxins). Getting into the tissues, these mediators irritate the nerve endings, provoke mucus secretion, spasms and contractions of micromuscles in the vessels. As a result, a person begins to sneeze, or develops a persistent, incurable runny nose, lacrimation, suffocation. In severe cases, such a biochemical reaction can end very sadly - anaphylactic shock.
- The immune response phase is slow. As soon as the mediators stop provoking inflammatory processes, hypersensitivity seems to subside. This is explained by the fact that the immune system sends lymphocytes, leukocytes, and all possible substances to the inflammation site to neutralize the problem. These cells begin to restore damaged tissue, replacing it with connective tissue. The slow reaction can last more than two days, and begins six hours after the acute phase.
Allergy manifestations are divided into categories – local or general.
Local signs:
- Swelling of the nasopharyngeal mucosa, rhinitis;
- Conjunctivitis;
- Respiratory allergy, bronchospasm, asthma;
- Ear pain, hearing loss;
- Skin rash, dermatitis, eczema;
- Headache.
Symptoms can be very diverse, but at the first slightest sign of their appearance, you should consult a doctor in order to stop the development of allergies in time and prevent serious consequences.