The essential oil from Piper solmsianum leaves and its major compound (sari
san) were tested to verify their influences upon mice behaviour. The essent
ial oil was obtained by hydrodistillation in a modified Clevenger extractor
and analysed by GC/ MS. This analysis revealed in the oil the presence of
monoterpenes, sesquiterpenes and of arylpropanoids. The compound sarisan, a
myristicin analogue, was isolated from the oil to perform the pharmacologi
cal tests. Emulsions of the oil and of sarisan (5.0 and 10.0% v/v) were use
d in the tests. Pentobarbital (30 mg/ kg s.c.) or diazepam (2.5 mg/ kg s.c.
) were tested as standard drugs to verify depressant or anxiolytic effects,
respectively. Both essential oil and sarisan showed to have exciting and d
epressant effects in the tested animals.