Prodromal itching in childhood asthma.

In a prospective study of 79 children with asthma, 26 had prodromal itching 1 - 30 min before the attack, and 17 had prodromal itching during the early part of the attack. The sensation lasted up to about 30 min. Scratch marks were seen in 5 patients. In 7 patients the itching was known to the child but had not been recognised by the parents. The site of itching was constant for each patient, being the anterior part of the neck in 14 patients and the upper part of the back in 9 patients. The pathogenesis of prodromal itching is obscure, but its recognition may be of diagnostic use when taking a history and may enable an attack of asthma to be aborted or treated more promptly.