Contact allergic dermatitis is an acute or chronic dermatitis that occurs at the contact site due to the contact of skin or mucosa with sensitizing substances. Chemical fiber clothing, hair dyes, cosmetics, etc. can all be allergenic substances. Most babies get sick within hours or days of contact with pathogenic substances.

Manifestations: Erythema, papules and papules with clear boundaries occurred at the contact site, and the itching was unbearable.

Treatment with antihistamines is ineffective.

Hereditary allergic dermatitis (atopic dermatitis) occurs frequently in infants, children and adolescents, and is a chronic disease that is easy to recur, also known as three-stage course of disease.

At the beginning of infancy (2 months-2 years old), dermatitis is not obvious, the skin is dry and red, mainly itchy, and the baby is crying; Erythema and papules can be seen in the future, and there will be blisters, exudates and scabs. In severe cases, almost all the body will have symptoms, especially in the joints of face, neck, knees and elbows.