The symptoms of an allergy most often affect the respiratory and olfactory apparatus. Characteristic is the occurrence of the symptoms in attacks. If there is an allergy to pollen or similar, a seasonal occurrence of the symptoms can be observed.
Typical are the months of March to August, while in autumn and winter there are no symptoms. Frequent symptoms are coughing, rhinitis with a practically chronic blocked nose as well as watery, itchy, reddened and sometimes swollen eyes. If there is a food allergy, an allergy to medicines or certain materials such as nickel, a skin rash typically occurs.
For contact allergy (for example, contact with a certain metal), it is typical that a rash occurs at the point of contact. In the case of a drug or food allergy, on the other hand, the skin rash may be generalised. In the case of a food allergy, diarrhoea or abdominal cramps are also common, and sometimes nausea and even vomiting can occur.
An allergy can also lead to allergic asthma. This is often the case with a dust mite or pollen allergy. Excessive contact with the allergen then leads to a seizure-like asthma attack with shortness of breath, whistling sounds when breathing out and coughing.
The children often feel anxious during a seizure. Coughing is a typical symptom of an allergy. The cough can be dry or slimy.
The cough occurs in attacks when the respiratory tract comes into contact with the allergen. In most cases the irritation of the cough is accompanied by difficulty in breathing out. The cough is usually strongest at night or in the morning, as the pollen load in the air is greatest at these times.
The same applies to an existing house dust mite allergy, which usually manifests itself at night because the mites are in bed in large numbers. If the cough is accompanied by a whistling sound when breathing, this can be a sign of allergic asthma, in which the respiratory tract becomes cramped. Why does an allergy lead to coughing in the first place?
One of the reasons is that the allergy mechanism releases substances that lead to a narrowing of the bronchi. Furthermore, it serves as a protective mechanism because the body tries to transport the inhaled allergen out of the body again by coughing. An allergic skin rash typically occurs in the context of contact allergy, food allergy or medication allergy.
Typically for a contact allergy, the rash is usually limited to the point of contact with the allergen, whereas a drug allergy results in a whole body rash. Such a rash sometimes develops as so-called hives. These are small elevations of the skin, so-called wheals, which are filled with liquid and itch.
If these raised areas are larger they are called angioedema. If such an angioedema develops in the pharynx, it is called a life-threatening Quincke’s edema, which can considerably impede breathing. The eyes are not affected by every allergy.
They are typically particularly involved in hay fever. In this case the nose is usually also involved and shows symptoms in the form of an inflammation of the nasal mucous membrane. Typical symptoms are itching of the eye, burning and increased lacrimation.
Reactively, the eyes are often reddened by the itching. In some children the eyelids are also swollen and/or the veins around the eye are congested, resulting in dark circles around the eyes. Because the nose is usually also congested, the increased tear fluid cannot drain off properly because the tear duct runs through the lower nasal concha. Affected people therefore often complain about watery eyes.