This research work was meant to explore the hypoglycemic potencies of different tropical herbal aqueous leaf extract of Vernonia
amygdalina (Bitter leaf), Phyllanthus amarus (Stone breaker) and Ocimum gratissimum (Sent leaf) on blood sugar level of alloxan
induced diabetic guinea pigs. Thirty-five guinea pigs of both male and female were randomly selected and grouped accordingly using
Glibenclamide solution (a known oral hypoglycemic drug) as a positive control and physiological solution (0.9% Normal Saline) as
a negative control. The average weight of the guinea pigs was 250g. Each guinea pig was made diabetic by induction with a single
dose of 5% alloxan monohydrate dissolved in 0.9% normal saline at 200mg/kg body weight intraperitoneally. This concentration
of alloxan used for diabetic induction in these guinea pigs was determined during the preliminary test. Three different groups had
oral administration of the aqueous leaf extract via Canula at 300mg/kg body weight per day for two weeks after alloxan induction.
The positive and negative control groups had oral administration of glibenclamide solution (a known oral hypoglycemic agent)
at 0.25mg/day and 0.9% NS (a physiological solution) at 15ml/day via canula for two weeks respectively. On the average, the
results of this study revealed appreciable percentage reduction of fasting blood sugar level of the diabetic guinea pigs that had
oral administration of aqueous leaf extracts of Phyllanthus amarus, Vernonia amygdalina and Ocimum gratissimum which was
comparable to the fasting blood sugar level of positive control group (Glibernclamide solution), thereby showing an appreciable
hypoglycemic effect. In conclusion, the z-test as a statistical test revealed a significant difference between the post induction fasting
blood sugar level and post aqueous leaf extract administration (p< 0.05).