Hippocratic screening of ethanolic extracts from two Tabernaemontana species.

Ethanolic extracts of roots, stems, leaves and flowers of Tabernaemontana divaricata and T. pandacaqui were studied by an observational (hippocratic) screening method in rats. Extracts of all plant parts caused sedation, decreased respiration and decreased skeletal muscle tone. Except for the leaf extract of T. pandacaqui, the extracts caused vasodilatation of ear vasculature. Analgesic activity was found for all extracts of both Tabernaemontana species, except for the flower extract of T. divaricata. Lethal doses of the extracts caused the animals to die from respiratory paralysis. Intensity of pharmacological activities was greater with the root and stem extracts. The extracts of T. pandacaqui were more potent than those of T. divaricata.