Incidences and types of Allergy

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Respiratory allergy (rhinoconjunctivitis and/or allergic asthma) is the most common allergic disease. It affects about 25% of the general population. It is followed by food allergy with an incidence of 2-3% and that of drugs with 0.5%.

Types of Allergy

Person with persistent cough

Respiratory allergy (rhinoconjunctivitis and/or allergic asthma). Allergic rhinitis is defined by the presence of sneezing, transparent or whitish mucus, itchy nose and/or obstruction. The reddening and itching of eyes are usually accompanied to a greater or lesser extent with the nasal symptoms. Allergic asthma is defined by the presence of wheezing in the chest, persistent cough and/or a feeling of breathlessness. The severity of the rhinoconjunctivitis and the asthma can be very different from one patient to another.

Nut allergy

Food allergies. The most common signs and symptoms include itching in the area of the mouth and throat (oropharyngeal), itching of the skin with reddening or hives (urticaria) or even localized swelling (angioedema) on the lips, eyelids and other skin areas; less frequently, gastrointestinal disorders (nausea, vomiting, abdominal pain) may occur. Another manifestation of food allergy is anaphylaxis. Anaphylaxis is a serious reaction ‑it can affect a person’s life‑ that appears quickly after coming into contact with the allergen and that, in addition to affecting the skin, may be accompanied by gastrointestinal symptoms, respiratory tract involvement (choking, cough) and/or the cardiovascular system, in the form of hypotension, dizziness or loss of consciousness.


Drug allergy

Allergy to drugs. It manifests in the form of a local or general skin rash, itching or burning sensation (urticaria), or even anaphylaxis. 


Allergy to hymenoptera. The allergy to bee and/or wasp venom (insects of the group of hymenoptera) can manifest itself in the form of a gigantic local reaction at the point of the sting, or in the form of an urticaria and/or angio‑oedema or anaphylaxis.

Hives or allergic contact dermatitis on the arm

Contact allergic dermatitis. This is produced by direct contact of the skin with inert substances (metals, perfumes, cosmetics, rubber accelerating products, etc.). Depending on the evolution and severity, it may have mild manifestations, such as redness and subsequent decimation of the affected area, or vesicular lesions similar to a third-degree burn.


Substantiated information by:

Joan Bartra Tomàs
Rosa Maria Muñoz Cano

Published: 24 July 2019
Updated: 24 July 2019

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