The antispasmodic property of Costus aferethanol leaves extract (CALE) was investigated on isolated rabbit jejunum in exclusively in vitro experimental models. About 2-3cm of the rabbit jejunum was mounted in a 35ml organ bath containing tyrode solution bubbled with 95% Oxygen and 5% carbondioxide and was allowed to equilibrate for 20 minutes before administrations of selected agonists, antagonists and CALE with proper washing after each administration.Results obtained indicate that all doses of Acetylcholine and histamine increased the amplitude of rhythmic contractions of the jejunum significantly (P<0.05), while CALE causedsignificant (P<0.05) inhibition of both basal rhythmic contractions and Acetylcholine and histamine induced contractions with 114.3µg/ml of CALE inhibiting 2.86µg/ml of acetylcholine and histamine by 69.37 and 50.34% respectively. The effects of CALE compared favourably with those of atropine and promethazine and suggest that the extract may contain principles with antispasmodic property and may be of value in the management of diseases like diarrhea, incontinence, peptic ulcer, gastrointestinal cramps, gastritis and muscular spasms.
