 This alkaloid is the main toxic component of Calabash curare, and one of the most toxic plant alkaloids known to man.The lethal dose (LD50) for mice has been determined as 10 - 60 µg/kg by intravenous administration.It is a muscle relaxant that causes paralysis of skeletal muscle, which takes approximately 2 hours to recovery for a moderate dose, and 8 hours of total paralysis with a 20-fold paralytic dose.