In a double blind randomized clinical trial with two groups of 25 patient sreceiving 100 mg C. colocynthis fruit capsules or placebos three times a day, fasting blood glucose was significantly
Decreased following two months of C. colocynthis administration as compared to placebo (Huseini etal.,2009). In a randomized double-blind placebo-controlled clinical trial patients received hydroalcoholic extract of Vaccinium arctostaphylos (350mg, every 8 h for 2 months) or placebo along with anti- hyperglycemic drugs .The extract significantly reduced the blood fasting sugar levels as well as 2 hpostprandial glucose(Kianbakht et al.,2013).