We wished to determine whether nebulized sodium cromoglycate (SCG) has bronchodilator effects in very young children. In 18 children born prematurely and studied at a median of 15 months of age, thoracic gas volume (TGV) and airways resistance (Raw), were measured and hence specific airways conductance (sGaw) was calculated before (baseline) and after nebulized saline, and then after sodium cromoglycate. sGaw improved significantly in 10 infants after SCG, compared to only in two following saline. These preliminary results suggest that nebulized SCG may have an acute bronchodilator effect in some children born prematurely.