The antitussive efficacy and tolerability of dropropizine and of its enantiomer levodropropizine were evaluated in children with non-productive cough; 258 were evaluable for tolerability and 254 for efficacy. Patients randomly received either 1 mg/kg dropropizine or 2 mg/kg levodropropizine orally, three times daily for 3 days. There were statistically significant decreases in the frequency of coughing spells and nocturnal awakenings after both levodropropizine and dropropizine treatments (P < 0.001). Gastro-intestinal symptoms were mild in the two groups; somnolence was twice as frequent in the dropropizine group (10.3% vs 5.3%) and the difference is clinically relevant, though not statistically significant. Levodropropizine is as effective as an antitussive as dropropizine, but appears to carry a lower risk of daytime somnolence.