What is Allergy?

Allergy is an excessive and abnormal reaction of the body's immune system to some non-harmful substances (called allergens) in the environment. Although itching, runny nose, sneezing can occur in the skin when the name of allergy is called, there are many different allergic diseases according to the organ affected by the allergy. These include allergic bronchial asthma, allergic nose and eye conjunctivitis (shamannesis, spring fever, medically known as allergic rhinoconjunctivitis), food allergy, drug allergy, allergy (infancy eczema, eczema, atopic dermatitis with its medical name), animal allergy, insect allergy and occupational allergies to the substances in the working environment.

Allergic diseases are chronic diseases that develop with the coexistence of genetic predisposition and environmental factors. Therefore, they are not transmitted from person to person. Allergic diseases are seen more frequently in children of parents with allergic diseases than in children in normal society. For example, while the frequency and risk of allergic disease in a society in general (allergic asthma, hay fever...) is observed at an average of 20%, if one of the parents has an allergic disease, the risk for the child is 45%. It goes up to 70.

What is an allergen?
Substances in the environment that cause allergic reactions in the body are called. All of them cause allergic symptoms according to the organ they affect. Those that are most common in the environment and cause allergic diseases are called "aeroallergens". These are divided into two as indoor and outdoor allergens. The best example of indoor allergens is house dust mites, and the best example of outdoor allergens is pollen.


It is the dust released into the environment during the reproduction periods of grass, trees and flowers. Therefore, allergic complaints related to pollen occur in the spring months, when the flowers of these plants bloom. The type of pollen that is allergic is related to the vegetation in that region. For example, the olive tree, which is common in the Mediterranean region, is a common cause of hay fever in the region. Because pollens have large particles, they are kept in the nose and cause allergic rhinitis (hay fever).


They have the feature of being indoor and outdoor allergen. These are microbes that often live on organic items, food, plants and animals outside the home. They have nothing to do with edible fungi. Mold fungi reproduce in moist, organic food residues. From here, they release fungal spores into the air, which continue to reproduce abundantly. These are smaller cells than pollans. They mix easily with air and are transported. Where they breed, yellow, green etc. they create color. Although they can reproduce and leave spores throughout the year, their reproduction is at the highest level in the spring and summer months when the weather is warm and moderate winds are experienced. They cannot reproduce at low temperatures in winter, and they do not leave spores that cause allergies. Since they have a very small structure, they suffer from both allergic rhinitis and allergic asthma.


The most common is cat and dog allergy. The cat's skin rash, fur, saliva, urine and feces can be allergic. These can lead to allergic rhinitis, eczema and sometimes asthma. Although the symptoms are often in close contact with the cat in the home, it can also be in the external environment. Even if the cat is removed from the house, its allergens can remain in the same environment for 6 months or longer. The dog is also allergic to similar materials. In addition, allergies can be detected in laboratory workers against poultry, birds, sheep and many animals, even animals used in laboratory experiments.


It is the most common allergy. Allergy develops against some proteinaceous substances in the bee's venom. In order for this to develop, the person must first encounter this poison and become sensitized, and then encounter it again. The most feared aspect of bee allergy is that it can cause a fatal allergic shock called anaphylaxis, as the allergen enters the body directly with the sting of the bee. Allergy can develop against all types of bees. In addition, allergies may develop against the poisons and saliva of mosquitoes and all stinging animals. The allergic reaction that develops can range from just a wide skin rash to death. In addition, cockroach allergy can be counted in this group.

Cockroach excrement is allergic. It can cause asthma, allergic rhinitis and eczema.


The most commonly known is penicillin. However, it should be known that the most common drug allergen is not penicillin. All drugs can cause allergies as much as penicillin. Antibiotics, painkillers, insulin, hormone preparations are the leading ones. Drug-induced anaphylaxis is not a very common condition.


The most common is cow's milk for children. This is because cow's milk contains a protein called beta-lactoglobulin, which is not found in breast milk. In addition, seafood, eggs, nuts, peanuts, cereals, meat, bananas, kiwis, etc. are the causes of other food allergies. Sometimes, by ingesting environmental allergens on foods, it can cause that food to be mistakenly perceived as allergic. Food allergy cases usually present with abdominal pain, diarrhea, vomiting, and mouth swelling. However, it may also present with only growth retardation, inability to gain weight, allergic asthma, exercise shock, hay fever or allergic eczema shock, especially in children. While the reaction to cow's milk, egg and some food allergies is not seen after childhood, others continue for life.

Elimination (protection from allergens)
It is to prevent the patient from coming into contact with allergens to which he is sensitive. This topic is very important. Because in many allergic diseases, complaints usually develop after contact with allergen.

For example, the application of methods to prevent exposure to mites in the home of a patient with allergic rhinitis due to mites will also prevent allergic rhinitis complaints.

The only treatment for food allergy is to not eat the foods that the patient is allergic to. The most effective treatment method for drug allergies is not to use the drug that causes the allergy.

Pharmacotherapy (Medication):
To control the signs and symptoms of the disease with drugs is to treat. For example, relieving urticaria (hives) complaints with antihistamines, controlling complaints with short and long-acting bronchodilators and corticosteroids in asthmatics and preventing attacks.

Immunotherapy (vaccine therapy)
The vaccine is known as a cure. It is the injection of increasing doses of allergens to which the patient is sensitive. The aim is to develop tolerance to allergens and to prevent the patient from creating an allergic reaction when he encounters substances to which he is allergic.

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