Abstract
The polyherbal bitters are herbal galenicals commonly used by diabetic patients, because they are claimed to have antidiabetic potentials. Promoters of the bitters claim that, the bitters being of natural origin could be concurrently administered with conventional therapeutic drugs with no adverse effects. This research was aimed at assessing the effect(s) or otherwise of the co-administration of two popular bitters in Nigeria market Swedish bitter (SB) and Yoyo bitters (YB) and two therapeutic antidiabetic drugs metformin (MET) and glibenclamide (GLI) on the hypoglycemic and lipid profile in alloxan induced diabetic rats. Fifty four diabetic rats of both sexes weighing between 160g to 230g were divided into nine groups with six animals per group. Therapeutic doses of the bitters alone and in combination with GLI and MET corresponding to the body weight of the animals were administered orally to the different groups daily for 14 days. After an overnight fast, fasting blood glucose levels were obtained by tail tipping method on days 0, 1, 3, 5, 8, 11 and 14. On the 14th day the rats were sacrificed and blood collected by cardiac puncture. The blood was centrifuged and the plasma collected was analyzed for lipid profile. The results obtained indicated that GLI, MET, SB and YB all caused a significant decrease (p<0.05) in blood glucose during the period of studies in all treated groups compared to the control group. There was a synergistic effect on the hypoglycemic efficacy of GLI when GLI was co-administered with YB, but there was a decrease in hypoglycemic efficacy of MET when it was co-administered with YB. There was no effect when MET and GLI were respectively co-administered with SB. GLI, MET and the bitters caused an increase in the lipid profile when administered as a mono-therapy and in combination with each other. From the results of these studies, we conclude that, some bitters have hypoglycemic potency comparable to most conventional therapeutic drugs, however it is not safe to administer any of the bitters concurrently with therapeutic drugs since the effect on their hypoglycemic parameter is not predictable.
