To estimate the efficacy of ambroxol for clinical use in prenatal prevention and postnatal therapy of hyaline membrane disease (HMD) all available experimental and clinical data were reviewed. The administration of ambroxol in animals has a certain promoting influence on lung maturation, a high specificity to lung tissue and a favourable relationship between intended action and negative adverse effects. In clinical studies concerning the prevention of HMD, ambroxol increases the values of amniotic fluid parameters used for estimation of lung maturity and reduces the incidence of HMD at least as effectively as corticosteroids. The number of infants at less than 33 gestational weeks in these reports is small, and further studies will have to confirm the results. Ambroxol applied postnatally has beneficial effects on the course of severe HMD by increasing survival rate, by decreasing duration of oxygen need and artificial ventilation and by improving compliance. Pharmacological studies in preterm HMD-infants showed no influence of ambroxol on blood pressure and heart rate. In 3 of 8 newborns a transient increase of transcutaneous oxygen tension was seen during infusion of ambroxol. Ambroxol is quickly bound to tissue receptors which release it continuously indicating that repeated applications are as effective as continuous infusion.