The present study was undertaken to validate some of the folkloric claims about the effectiveness of the use of a Myrtus communis L. crude methanol extract (Mc.Cr) in gastrointestinal, respiratory and vascular diseases. Mc.Cr caused complete relaxation of spontaneous and K+ (80 mM)-induced contractions in isolated rabbit jejunum. It caused right ward parallel shift of calcium concentration response curves. Mc.Cr exhibited relaxant effect on CCh- and K+ (80 mM)- induced contractions in isolated rabbit tracheal preparations. Furthermore, Mc.Cr caused relaxation of phenylephrine (1 μM)- and K+ (80 mM)-induced contractions in isolated rabbit aorta preparations. These effects were similar to verapamil, a standard calcium channel blocker. These findings could be the basis for explaining the spasmolytic, bronchodilator and vasodilator activities of the extract, through a possible calcium channel blocking activity.