PHARMACOLOGY

Pharmacotherapeutic Group: Oral hypoglycemic agent

Pharmacodynamic properties:  Glimepiride is an orally active hypoglycaemic substance belonging to the sulphonylurea group. Glimepiride binds to ATP-sensitive potassium channel receptors on the pancreatic cell surface, reducing potassium conductance. Closing of potassium channel induces depolarisation of the beta cell and results in calcium ion influx through voltage sensitive calcium channels. This increase in intracellular calcium ion leads to insulin release through exocytosis. The extrapancreatic effects are it also increases insulin sensitivity in the peripheral tissue and a decrease insulin uptake by the liver. Glimepiride inhibits the glucose production which in  turn inhibits gluconeogenesis.

Pharmacokinetic properties: Onset: Peak effect: 2-3 hr; Duration of action: 24 hr; Absorption: Completely absorbed from the GI tract after oral admin; Distribution: Highly protein bound; Metabolism: Hepatic metabolism to 2 main metabolites; Excretion: 60% excreted in urine and 40% in faeces (as metabolites); Elimination half life: about 9 hr.

 INDICATIONS :  Type 2 Diabetes Mellitus, Prevention of diabetic complication

 ADVERSE DRUG REACTIONS :  Vomiting, GI pain, diarrhoea; pruritus, erythema, urticaria, morbilliform, maculopapular eruptions; leukopenia, agranulocytosis, thrombocytopenia, haemolytic anaemia, aplastic anaemia and pancytopenia; hyponatraemia; changes in accommodation, blurred vision, jaundice.

DRUG INTERACTIONS :  Hypoglycemic effect potentiated by NSAIDs, salicylates, sulphonamides, chloramphenicol, coumarin, probenecid, fibric acid derivatives, pegvisomant, TCAs, MAOIs and β-adrenergic blocker. Thiazides and other diuretics, corticosteroids, phenothiazines, thyroid products, oestrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, rifampicin, and isoniazid may reduce hypoglycaemic effect of glimepiride. May increase the serum levels of ciclosporin. Serum levels may be increased by fluconazole.

PRESENTATION