Glipizide is an oral blood glucose lowering drug of the sulfonylurea class. It is characterized by its poor aqueous solubility. To
overcome this problem in addition to improve the dissolution behaviour of glipizide, different loaded mixtures of glipizide with
fenugreek or avicel PH 101 was prepared using different techniques (physical, ground mixtures, adsorbate and co-adsorbate systems).
The surface solid dispersions was prepared by solvent evaporation method then formulated into capsules. The interaction between
drug and the used excipients was performed using Fourier Transform Infrared (FT-IR) and Differential Scanning Calorimetry (DSC).
In vitro dissolution study was performed for glipizide loaded mixtures and also for the prepared capsules in 0.1N HCl using a standard
USP II dissolution apparatus. It was found that the dissolution rate of drug from solid dispersions was higher than the other prepared
systems and intact drug, where release rate of glipizide from prepared capsules containing co-adsorbate system of glipizide with
fenugreek at the ratio of (1:5:100, drug: tween 80: fenugreek w/w) is significantly higher than that obtained with avicel PH 101. In
vivo testing of the selected prepared glipizide capsules containing glipizide solid dispersion with fenugreek was carried out on nine
Newzeland rabbits. It was found that prepared glipizide capsules produce significant hypoglycaemic effect comparing with the
commercial product Minidiab®
. Clinical study was performed on fifteen type II diabetic human volunteers. The results showed a
significant decrease in PPBGL of patients who receive capsules containing glipizide solid dispersion with fenugreek rather than those
receiving glipizide commercial product Minidiab.