Multiallergy

Multiallergy is the coexistence of two or more allergic diseases within a single individual. Commonly observed conditions include allergic rhinitis, asthma, atopic dermatitis (eczema), food allergy, and drug allergy. The term describes a pattern of atopy rather than a single disease, and it is frequently identified in people with multiple allergic manifestations across childhood and adulthood.

There is no universal definition of multiallergy; it is used to describe the coexistence of two or more allergic diseases in one person. The pattern is common in pediatric populations and can persist into adulthood. Prevalence estimates vary by region and criteria, and the presence of multiallergy often prompts clinicians to monitor for additional sensitizations or comorbid conditions.

Pathophysiology involves genetic predisposition and environmental exposures that promote a broad IgE-mediated and inflammatory response. Shared mechanisms include a tendency toward Th2-dominated immunity, skin barrier defects in atopic dermatitis, and sensitization to multiple allergens. Early life factors, such as mode of delivery, infections, and diet, may influence the development of multiple allergic diseases.

Diagnosis requires an integrated assessment of each condition. Food allergies are confirmed with supervised oral food challenges when needed; skin prick testing or serum-specific IgE testing supports other allergies. Management emphasizes avoidance of triggers, symptom control with appropriate medications, and consideration of immunotherapy (for certain allergens) to reduce sensitivity. Regular follow-up helps adapt treatment as conditions change.

Outcomes vary widely. Some individuals experience persistent or evolving allergic diseases, while others outgrow certain allergies. Multiallergy can impact daily functioning and quality of life, underscoring the importance of coordinated care among primary care providers and allergy specialists, as well as patient education and emergency planning for potential anaphylaxis.