The family includes species considered to be medicinal. Their essential oil is used for headaches, colds, cough, and bronchitis. Cedar trees like () are commonly found in urban areas. We investigated whether exerts some of its effects by modifying airway smooth muscle (ASM) contractility. The leaves of (363 g) were pulverized mechanically, and extracts were obtained by successive maceration 1:10 (:) with methanol/CHCl. Guinea pig tracheal rings were contracted with KCl, tetraethylammonium (TEA), histamine (HIS), or carbachol (Cch) in organ baths. In the Cch experiments, tissues were pre-incubated with D-600, an antagonist of L-type voltage-dependent Ca channels (L-VDCC) before the addition of . Interestingly, at different concentrations, diminished the tracheal contractions induced by KCl, TEA, HIS, and Cch. In ASM cells, significantly diminished L-type Ca currents. ASM cells stimulated with Cch produced a transient Ca peak followed by a sustained plateau maintained by L-VDCC and store-operated Ca channels (SOCC). almost abolished this last response. These results show that , and its active metabolite quercetin, relax the ASM by inhibiting the L-VDCC and SOCC; further studies must be performed to obtain the complete set of metabolites of the extract and study at length their pharmacological properties.