Eczema, Allergies, and Asthma: Understanding the Atopic March in Children

What the atopic march describes

The atopic march refers to the tendency for children with a genetic predisposition to allergic disease to develop conditions in a rough developmental sequence 1Ref 1Dhar S, Jagadeesan S (2022).Atopic March: Dermatologic Perspectives.Sequence and mechanisms of the atopic march, filaggrin mutations, the dual allergen exposure hypothesis, and epidemiological data on progression rates. The trajectory is not inevitable or universal — it describes a statistical pattern across populations, not a certainty for any individual child:

• Eczema often appears in the first months of life, reflecting a skin barrier that is less effective at keeping allergens out and moisture in.
• Food allergy tends to emerge in infancy and early toddlerhood, often in children with moderate-to-severe eczema.
• Allergic rhinitis (hay fever) typically develops after age three or four, once the child has had several pollen seasons to become sensitized.
• Asthma may appear alongside or after the allergic nasal disease, often in children who already have multiple other atopic conditions.

Research suggests that only a subset of children with atopic dermatitis — approximately one in four — transition to at least one other allergic phenotype 1Ref 1Dhar S, Jagadeesan S (2022).Atopic March: Dermatologic Perspectives.Sequence and mechanisms of the atopic march, filaggrin mutations, the dual allergen exposure hypothesis, and epidemiological data on progression rates. Genetics strongly shapes this predisposition, as mutations in genes affecting the skin barrier (such as filaggrin) increase risk for the full sequence.

The role of skin barrier in early allergy

Research over the past decade has shifted understanding of how food allergy develops in some children. Rather than sensitization occurring only through eating food, there is evidence that allergen exposure through an inflamed or impaired skin barrier can trigger immune sensitization in a way that favors allergy rather than tolerance — a pattern described as the "dual allergen exposure hypothesis" 1Ref 1Dhar S, Jagadeesan S (2022).Atopic March: Dermatologic Perspectives.Sequence and mechanisms of the atopic march, filaggrin mutations, the dual allergen exposure hypothesis, and epidemiological data on progression rates. This partially explains why babies with poorly controlled eczema have elevated rates of food allergy. It is one reason why effective eczema treatment — keeping the skin barrier intact and inflammation under control with regular moisturizing and prescribed topical treatments — is considered important beyond comfort alone.

Early peanut introduction: a landmark prevention finding

The LEAP (Learning Early About Peanut) trial demonstrated that early, sustained consumption of peanut products was associated with a substantial decrease in peanut allergy development in high-risk infants. In the trial, only 3.2% of infants randomized to early peanut consumption developed peanut allergy by age five, compared with 17.2% in the avoidance group — approximately an 80% reduction in relative risk 2Ref 2Du Toit G, Roberts G, Sayre PH, et al.; LEAP Study Team (2015).Randomized Trial of Peanut Consumption in Infants at Risk for Peanut Allergy.Early peanut introduction in high-risk infants (severe eczema or egg allergy) reduced peanut allergy prevalence by ~80% at age 5 compared with avoidance.

Current guidelines from major allergy organizations recommend early introduction of peanut for infants with severe eczema or egg allergy, often between four and six months of age, to reduce the risk of peanut allergy. The appropriate timing and method depend on the severity of the eczema and the results of any initial evaluation — discuss the specific approach with your child's pediatrician or allergist before introducing peanut in this context, as the guidance is different from the general approach for low-risk infants.

What parents can watch for

Parents of a child with established eczema or food allergy do not need to be anxious about the march, but being alert to new symptoms can lead to earlier diagnosis and management:

• A toddler with eczema who develops hives or vomiting after a new food deserves evaluation for food allergy.
• A preschooler with food allergy who starts sneezing and having itchy eyes every spring deserves evaluation for allergic rhinitis.
• A school-age child with hay fever who begins coughing with exercise or at night should be screened for asthma 3Ref 3American Academy of Pediatrics (2024).Food Allergies in Children: Causes, Symptoms, Diagnosis & Treatment.Coordinated management of multiple atopic conditions and the connection between allergic rhinitis and asthma control in children.

None of these are emergencies to raise proactively, but they are worth mentioning at well-child visits or when symptoms are noticed.

Managing multiple atopic conditions simultaneously

Children with more than one atopic condition often benefit from coordinated care — a pediatrician who holds the overview, a pediatric allergist who manages the allergy and immunotherapy picture, and a pediatric dermatologist if eczema is severe or complex. Management of one condition affects others: better eczema control can reduce food sensitization risk; treating allergic rhinitis may reduce asthma exacerbations; identifying and avoiding food allergens reduces the overall inflammatory burden 3Ref 3American Academy of Pediatrics (2024).Food Allergies in Children: Causes, Symptoms, Diagnosis & Treatment.Coordinated management of multiple atopic conditions and the connection between allergic rhinitis and asthma control in children. An integrated view prevents the child from being treated in isolated silos.