A comparison between metformin and garlic on alloxan-induced diabetic dogs

The present study was carried out to investigate the hypoglycaemic effects of metformin and garlic (Allium sativum Linn) in alloxan-induced diabetic dogs. The anti-diabetic activity of garlic had never been investigated in experimental diabetic dogs. Twenty-one adult dogs were randomly allocated into three equal groups consisting of seven dogs. The first group was the diabetic control, the second was the metformin treated and the third was the garlic-treated group. This study aimed to test 14-day oral administration of garlic (100 mg/kg) for its effects in alloxan-induced diabetic dogs in comparison with metformin (1,700 mg/dog/day) anti-diabetic activity. The mean decrease in blood glucose was 9. 27 mg/dl for metformin and 25. 93 mg/dl for garlic. The results showed that treatment with metformin non-significantly reduced blood glucose level (p > 0. 05) and significantly increased serum insulin level in diabetic dogs (p < 0. 05). In contrast to metformin, garlic resulted in a significant decrease in the level of blood glucose, with a concomitant significant increase in the serum insulin level in diabetic dogs (p < 0. 05). Garlic had a mild but significant blood glucose-lowering effect and the long-term use of this agent may be advantageous, over chemical drugs, in alleviating some of the chronic diseases and complications caused by diabetes. © 2011 Springer-Verlag London Limited.