Antispasmodic activity of essential oil from Lippia dulcis Trev.

AIM OF THIS STUDY: To investigate the essential oil of Lippia dulcis Trev. (Verbenaceae) that is traditionally used in the treatment of cough, colds, bronchitis, asthma, and colic in Middle America for antispasmodic activity. MATERIALS AND METHODS: We used a porcine bronchial bioassay to study contractile responses to carbachol and histamine in the absence or presence of the essential oil. RESULTS: The essential oil showed anti-histaminergic and anti-cholinergic activities at 100 microg/ml. CONCLUSIONS: The anti-histaminergic and anti-cholinergic activities of the essential oil of Lippia dulcis support the rational use of the plant or plant extracts to treat bronchospasm.