The absence of antagonism between extracts of Clinacanthus nutans Burm. and Naja naja siamensis venom

Abstract

Clinacanthus nutans Burm., a herb reputed in Thialand and Malaysia to be 'snakebite antidote' has been tested in vitro and in vivo for antivenin activity. The aqueous extract of C. nutans leaves has been found to have no effect on the inhibition of neuromuscular transmission produced by purified Naja naja siamensis neurotoxin in isolated rat phrenic nerve diaphragm preparations. The extract of C. nutans, when given orally or intraperitoneally, are ineffective in prolonging the survival time of experimental mice receiving lethal doses of N.n. siamensis crude venom. Oral administrations of the herb extracts pretreated with α-amylase or β-amylase also fail to protect the animals. It is concluded that the extract of C. nutans cannot antagonize the action of cobra venom.