Influence of age and severity of dermatitis on the percutaneous absorption of hydrocortisone in children.

The results of 55 4-h hydrocortisone absorption tests in 38 children with atopic or seborrhoeic dermatitis were analysed to evaluate the effect of age and severity of the dermatitis on percutaneous absorption of hydrocortisone. The children were divided into three groups on the basis of the severity of the dermatitis. The absorption of hydrocortisone caused a significantly higher mean rise of serum cortisol in 20 children with severe dermatitis (Group A) than in 17 children with moderate dermatitis (Group B). The mean post-application rise of serum cortisol in 18 children with mild dermatitis (Group C) was significantly lower than in the children with moderate dermatitis. There was a significant negative linear correlation between age and the post-application rise of serum cortisol in Groups A and C. In these groups the mean post-application rise of serum cortisol was significantly higher in children aged under 18 months than in children aged 18 months or over. Severe widespread dermatitis and an age under 18 months are two relevant risk factors in the topical use of hydrocortisone.