Improved effect of glibenclamide on administration before breakfast.

In an attempt to assess whether intake of glibenclamide before meals would improve its therapeutic capacity, the present investigation compared the effect of glibenclamide 2.5 mg t.i.d. given before and together with meals. In addition, these effects were compared with that of glibenclamide given as a single morning dose of 7.5 mg. The subjects studied were six Type 2 diabetics not previously exposed to sulphonylurea drugs. Irrespective of dosage and mode of administration, addition of glibenclamide to a standardized breakfast, lunch and dinner enhanced plasma IRI concentrations and reduced blood glucose concentrations as compared to administration of meals without the drug. The different modes of glibenclamide administration did not differ significantly with respect to IRI responses. However the blood glucose reduction after breakfast was significantly greater when glibenclamide 2.5 mg had been given before the meal than when 2.5 or 7.5 mg were given with the meal; a similar, but non-significant tendency was observed after lung; no consistent difference was seen after dinner. Food intake did not affect glibenclamide kinetics. It appears that administration of glibenclamide 2.5 mg before breakfast improved glucose utilization following the breakfast load, due to earlier attainment of an effective concentration of glibenclamide.