Gliclazide is a second-generation sulfonylurea oral hypoglycemic agent used in the management of Type 2 Diabetes Mellitus (T2DM). The 60mg strength is a modified-release (MR) formulation designed to provide a sustained 24-hour glycemic control with once-daily dosing. It acts primarily by stimulating insulin secretion from pancreatic beta cells. It is widely prescribed in India due to its efficacy, low risk of hypoglycemia compared to other sulfonylureas, and potential extra-pancreatic benefits.
Adult: Initial dose: 30-60 mg once daily with breakfast. The 60mg MR tablet is a once-daily formulation. Dose can be titrated based on glycemic response in increments of 30 mg every 2-4 weeks. Usual maintenance dose: 60-120 mg once daily. Maximum recommended dose: 120 mg once daily.
Note: Swallow the 60mg MR tablet whole with a glass of water, preferably with or just after breakfast. Do not crush, chew, or break the tablet. Maintain a regular meal schedule to avoid hypoglycemia. Monitor blood glucose regularly.
Gliclazide lowers blood glucose primarily by stimulating the release of insulin from functional pancreatic beta cells. It binds to the sulfonylurea receptor 1 (SUR1) subunit of the ATP-sensitive potassium (K-ATP) channels on the beta cell membrane. This binding causes channel closure, preventing potassium efflux, leading to depolarization of the cell membrane. Depolarization opens voltage-dependent calcium channels, resulting in an influx of calcium ions. The increased intracellular calcium concentration triggers the exocytosis of insulin-containing secretory granules.
Pregnancy: Category C (US FDA). Contraindicated. Insulin is the drug of choice for glycemic control during pregnancy. Sulfonylureas may cause neonatal hypoglycemia if used near delivery.
Driving: Caution advised. Gliclazide can cause dizziness, headache, and visual disturbances, especially during initial therapy or dose adjustment. The risk of hypoglycemia may impair the ability to concentrate and react, posing a danger while driving or operating machinery.
| Other Anti-diabetics (Insulin, Metformin, etc.) | Increased risk of hypoglycemia | Major |
| Beta-blockers (e.g., Propranolol) | Masked hypoglycemic symptoms (tachycardia); may potentiate hypoglycemic effect | Moderate |
| Fluconazole, Miconazole (topical/oral) | Potentiate hypoglycemic effect (CYP2C9 inhibition) | Major |
| Warfarin | Increased anticoagulant effect (displacement from protein binding) | Moderate |
| Rifampicin | Reduced efficacy of Gliclazide (CYP2C9 induction) | Moderate |
| ACE Inhibitors (e.g., Enalapril) | Increased risk of hypoglycemia | Moderate |
| NSAIDs (e.g., Ibuprofen) | Increased hypoglycemic effect (displacement from protein binding) | Moderate |
| Sulfonamides (e.g., Co-trimoxazole) | Increased hypoglycemic effect | Major |
| Alcohol | Increased risk of hypoglycemia or disulfiram-like reaction (flushing, nausea) | Major |
| Thiazide diuretics (e.g., Hydrochlorothiazide) | Reduced hypoglycemic effect (hyperglycemia) | Moderate |
Same composition (Gliclazide (60mg)), different brands: