Allergies in puberty: Why the immune system takes new paths in adolescence

Puberty is a period of profound change. Alongside marked physical changes and neurobiological maturation, the immune system also undergoes a significant transformation during adolescence. Many families notice that previously unknown allergic symptoms appear for the first time in this phase of life, or that existing conditions such as atopic dermatitis or hay fever suddenly change. A well-founded look at the hormonal and immunological mechanisms helps to classify symptoms correctly and counteract them therapeutically. 
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<li> The immune–hormone axis: How sex hormones influence the immune system</li>
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That allergies often change in their expression during puberty is no coincidence, but the result of an intense interaction between the endocrine system (hormonal system) and the immune system. The sex hormones released in increased amounts during puberty act directly on the cells of the immune defence. 
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<li>The influence of oestrogens: Oestrogens tend to stimulate type 2 T helper cells (Th2 response). These Th2 cells play a key role in the development of allergic reactions, as they promote the production of immunoglobulin E (IgE). This helps explain, among other things, why girls from puberty onwards are more often affected by newly developing allergic asthma or intensified hay fever (allergic rhinitis). </li>
<li>The role of testosterone: Androgens such as testosterone, by contrast, tend to have immunomodulatory and anti-inflammatory properties. They can dampen the Th2 response. In boys, the pubertal rise in testosterone levels therefore not infrequently leads to a noticeable improvement in pre-existing allergic conditions. </li>
<li>Changes in the skin barrier: The hormonal shift also affects sebum production and the lipid content of the skin. While the tendency to skin blemishes increases, childhood atopic dermatitis (atopic eczema) may either improve significantly during puberty or change its distribution pattern on the body (e.g., increased involvement of the face and neck). </li>
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<li> The “floor change”: From childhood eczema to allergic asthma</li>
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In allergology, the term allergic march describes the typical sequence of allergic diseases over the course of childhood and adolescence. While food allergies and atopic eczema are at the forefront in infancy and early childhood, with increasing age the focus often shifts to the airways. 
During puberty, untreated hay fever carries the risk of a so-called progression to the lower airways: the allergic inflammation migrates from the upper airways (nose and throat) to the lower airways (bronchi). Symptoms such as persistent irritative cough during physical exertion, a feeling of tightness in the chest, or wheezing breath sounds (wheezing) are serious signs of developing allergic asthma. 
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<li> Typical symptom patterns and how to differentiate them</li>
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The manifestation of allergies in adolescents is diverse. Careful observation helps to distinguish allergic reactions from infections or puberty-related skin changes: 
<h4 data-path-to-node="8">Allergic rhinitis (hay fever)</h4>
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Typical key symptoms: Sudden bouts of sneezing, watery runny nose, itchy and watery eyes. Unlike a common cold, there is usually no fever, and the nasal discharge remains clear. 
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Possible triggers during puberty: Tree pollen, grasses, house dust mites, animal dander.
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<h4 data-path-to-node="10">Cross-allergies (oral allergy syndrome / OAS)</h4>
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Typical key symptoms: Itching or swelling of the lips, tongue and palate that occurs directly after eating certain raw fruits/vegetables or nuts.
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Possible triggers during puberty: Botanical relatedness between inhalant allergens and foods (e.g., the link between birch pollen and eating apples or hazelnuts).
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<h4 data-path-to-node="12">Atopic eczema (atopic dermatitis)</h4>
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Typical key symptoms: Dry, scaly and intensely itchy patches of skin; typically located in the flexures (inner elbows, backs of the knees), on the hands or on the face. To be distinguished from classic pubertal acne, which is primarily caused by overactive sebaceous glands. 
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Possible triggers during puberty: Emotional stress, mechanical irritation, certain cosmetics, perfumes or synthetic textiles.
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<h4 data-path-to-node="14">Allergic asthma</h4>
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Typical key symptoms: Dry cough (especially at night or during physical exertion), persistent shortness of breath, and audible wheezing (a whistling sound when breathing out).
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Possible triggers during puberty: Inhaled allergens (such as pollen or mites), cold air, and physical exertion.
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<li> Diagnostics and modern treatment approaches</li>
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If an allergy is suspected in adolescents, a structured allergology work-up should be carried out in a specialist practice.
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<li>Medical history & symptom diary: Recording the exact symptom pattern, seasonal dependencies, and allergies in the family.</li>
<li>Skin and blood tests: The prick test on the skin and measurement of specific IgE in the blood (RAST test) identify the triggering allergens.</li>
<li>Symptomatic treatment: The use of modern, non-sedating antihistamines and topical glucocorticoid nasal sprays provides rapid relief for acute symptoms.</li>
<li>Causal therapy (disease-modifying): Specific immunotherapy (SIT), or hyposensitisation, is the only causal treatment method. The allergen is administered to the immune system in increasing or constant doses over around three years (subcutaneously as an injection or sublingually as a tablet/drops). The aim is to desensitise the immune system in order to prevent progression to the lower airways and to drastically reduce the need for medication in the long term. </li>
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Conclusion
Allergies in puberty are not a static condition, but a dynamic process that is strongly influenced by hormonal maturation. While some symptoms in boys may improve due to the influence of testosterone, girls more often tend to experience an intensification of airway symptoms under the influence of oestrogen. Early allergological diagnostics are essential to minimise the risk of progression to the lower airways and to enable adolescents to enjoy unrestricted quality of life in everyday life and during sport through targeted therapeutic measures. 
Article by Dr Anne Stein – Specialist in Paediatrics & Adolescent Medicine, Allergology, Pulmonology