Glibenclamide is a sulfonylurea antidiabetic. Sulfonylureas appear to have several modes of action, apparently mediated by inhibition of ATP-sensitive potassium channels. Initially, secretion of insulin by functioning islet beta cells is increased. However, insulin secretion subsequently falls again but the hypoglycaemic effect persists and may be due to inhibition of hepatic glucose production and increased sensitivity to any available insulin.
Glibenclamide is readily absorbed from the gastro-intestinal tract, peak plasma concentrations usually occurring within 2 to 4 hours, and is extensively bound to plasma proteins. Absorption may be slower in hyperglycaemic patients and may differ according to particle size of the preparation used. It is metabolised, almost completely, in the liver, the principal metabolite being only very weakly active. About 50% of a dose is excreted in the urine and 50% via the bile into the faeces.
Nogluc® is used in the treatment of Type 2 Diabetes Mellitus.
DOSAGE AND ADMINISTRATION:
Type 2 diabetes mellitus: 2.5 to 5mg daily with breakfast, depending on patient response adjusted every 7 days by increments of 2.5mg daily up to 15mg daily. Dose may be increased to 20mg. Doses greater than 10mg daily may be given in two divided doses.
CONTRA-INDICATIONS AND WARNINGS:
Sulfonylureas should not be used in type 1 diabetes mellitus. Use in type 2 diabetes mellitus is contra-indicated in patients with ketoacidosis and in those with severe infection, trauma, or other severe conditions where the sulfonylurea is unlikely to control the hyperglycaemia; insulin should be used in such situations. Insulin is also preferred for therapy during pregnancy. Sulfonylureas with a long half-life such as chlorpropamide or glibenclamide are associated with an increased risk of hypoglycaemia. They should therefore be avoided in patients with impairment of renal or hepatic function, and a similar precaution would tend to apply in other groups with an increased susceptibility to this effect, such as the elderly, debilitated or malnourished patients, and those with adrenal or pituitary insufficiency.