1. Clinical & Scientific Overview
Gliclazide (Immediate-Release & Modified-Release) (TIP-MED-000050, Reference Code [4.6]) is classified under
Antidiabetic Medicines, Insulins & GLP-1 Agonists (Ch 04) as a Second-Generation Sulfonylurea with Selective Pancreatic SUR1 Binding.
Within the Indian regulatory and compendial framework, it is governed under Schedule H & Schedule G Prescription Drug ('Caution: It is dangerous to take this preparation except under medical supervision' — Drugs Rules 1945).
Representative Indian Market Examples (Edition 2.7 Ch 04 [4.6], p. 47): Diamicron / Diamicron-XR / Diamicron-XR Mex (Serdia), Reclide / Reclide-MR (Dr. Reddy's), Glizid / Glizid-MR (Panacea), Glycinorm (Ipca) — Strengths & Dosage Forms: Immediate-Release (IR) Scored Tablets: 40 mg, 80 mg; Modified-Release (MR / XR) Tablets: 30 mg, 60 mg
Immediate-Release (IR) Scored Tablets: 40 mg, 80 mg; Modified-Release (MR / XR) Tablets: 30 mg, 60 mg
3. Mechanism of Action & Pharmacodynamics
Second-Generation Sulfonylurea with Selective Pancreatic SUR1 Binding acting on target receptor/enzyme pathways in Antidiabetic Medicines, Insulins & GLP-1 Agonists (Ch 04): clinical efficacy is mediated via Second-Generation Sulfonylurea with Selective Pancreatic SUR1 Binding for Type 2 diabetes mellitus inadequately controlled by diet, exercise, and metformin (preferred sulfonylurea in elderly and mild-to-moderate CKD due to inactive renal metabolites and lower hypoglycaemia rate)..
4. Therapeutic Indications & Evidence-Supported Uses
- Type 2 diabetes mellitus inadequately controlled by diet, exercise, and metformin (preferred sulfonylurea in elderly and mild-to-moderate CKD due to inactive renal metabolites and lower hypoglycaemia rate)
🇮🇳 Jurisdiction & Indication Note: Indications and schedules reflect Indian compendial and regulatory records (CDSCO / Indian Pharmacopoeia & NFI / NLEM 2022). Where international reference labels (US FDA DailyMed / NCBI StatPearls) are cited for pharmacokinetic or mechanistic parameters, international approvals do not automatically imply CDSCO approval in India.
5. Educational Dosage Context, Formulations & Administration
Educational Dosing & Regimen Summary: General Adult Reference: Formulation Equivalence Alert: Gliclazide 30 mg MR equals 80 mg IR! MR Regimen: 30 mg to 120 mg once daily at breakfast (max 120 mg MR/day). IR Regimen: 40 mg to 80 mg once daily at breakfast; doses of 160–320 mg/day are divided twice daily before breakfast and dinner. Follow physician prescription.
Administration & Meal Timing: Take WITH breakfast (for MR once daily) or immediately before/with breakfast and dinner (for IR twice daily). | MR: Once daily with breakfast. IR (>80 mg): Divided morning and evening with meals.
6. Pharmacokinetics, Metabolism & Renal/Hepatic Adjustment
Absorption, distribution, metabolism, and excretion follow class pharmacokinetic profile; verify patient renal/hepatic function.
Renal: Metabolised extensively in the liver to inactive metabolites (unlike glimepiride/glibenclamide which form active renal metabolites)—therefore safer in mild-to-moderate CKD (eGFR 30–60 mL/min) without dose adjustment, though hypoglycaemia vigilance remains essential; avoid if eGFR <30 mL/min. Hepatic: Contraindicated in severe hepatic insufficiency.
Renal: Metabolised extensively in the liver to inactive metabolites (unlike glimepiride/glibenclamide which form active renal metabolites)—therefore safer in mild-to-moderate CKD (eGFR 30–60 mL/min) without dose adjustment, though hypoglycaemia vigilance remains essential; avoid if eGFR <30 mL/min. Hepatic: Contraindicated in severe hepatic insufficiency.
Renal: Metabolised extensively in the liver to inactive metabolites (unlike glimepiride/glibenclamide which form active renal metabolites)—therefore safer in mild-to-moderate CKD (eGFR 30–60 mL/min) without dose adjustment, though hypoglycaemia vigilance remains essential; avoid if eGFR <30 mL/min. Hepatic: Contraindicated in severe hepatic insufficiency.
7. Contraindications, Precautions & High-Risk Warnings
- Contraindicated in Type 1 DM, DKA, severe hepatic failure, severe renal failure (eGFR <15–30 mL/min), pregnancy, lactation, and concurrent miconazole therapy. Caution in G6PD deficiency.
Key Clinical Precautions: Renal: Metabolised extensively in the liver to inactive metabolites (unlike glimepiride/glibenclamide which form active renal metabolites)—therefore safer in mild-to-moderate CKD (eGFR 30–60 mL/min) without dose adjustment, though hypoglycaemia vigilance remains essential; avoid if eGFR <30 mL/min. Hepatic: Contraindicated in severe hepatic insufficiency.
8. Adverse Effects Profile
- Hypoglycaemia (significantly lower incidence than glibenclamide or high-dose glimepiride), mild GI upset, weight gain.
- Severe hypoglycaemia, cholestatic hepatitis, rare haematological cytopenias, cutaneous hypersensitivity.
- Monitor for severe hypersensitivity, organ toxicity, or dose-limiting adverse events.
9. Major Drug–Drug, Drug–Food & Drug–Herb Interactions
- Miconazole (systemic or oral gel) is strictly contraindicated (causes profound, life-threatening hypoglycaemia via CYP2C9 inhibition)
- Fluconazole, phenylbutazone, cotrimoxazole, fluoroquinolones, clarithromycin, and alcohol potentiate hypoglycaemia
- Beta-blockers mask tachycardia/tremor signs of hypoglycaemia
- John's Wort and rifampicin reduce gliclazide levels
10. Clinical Monitoring, Patient Counselling & Storage
Clinical & Laboratory Monitoring: Monitor clinical response, baseline renal/hepatic parameters, and relevant serum biomarkers.
Pharmacist Patient Counselling Points:
- Patient Counselling Checklist: Verify carefully at the dispensing counter whether the prescription specifies MR/XR (30 mg or 60 mg) vs plain IR (40 mg or 80 mg). Swallow MR tablets whole (except specific scored Breakable MR tablets like Diamicron XR 60 mg, which may be halved along the score line per insert, never crushed). Always carry a glucose packet when going for morning walks.
- Meal & Clock Timing Instruction: Take WITH breakfast (for MR once daily) or immediately before/with breakfast and dinner (for IR twice daily). (MR: Once daily with breakfast. IR (>80 mg): Divided morning and evening with meals.)
- Missed Dose Protocol: If remembered during breakfast, take it; if breakfast is already over, skip the missed dose and resume the next scheduled dose with food.
- Geriatric Dispensing Pearl: Recommended by WHO and Indian geriatric guidelines as the sulfonylurea of choice in elderly patients when a secretagogue is required, because of its reversible pancreatic SUR1 receptor binding, lack of active renal metabolites, and lower nocturnal hypoglycaemia rate.
Storage, Stability & Dispensing Safeguards: Store below 25°C–30°C in original moisture- and light-resistant packaging out of reach of children. Available forms: Immediate-Release (IR) Scored Tablets: 40 mg, 80 mg; Modified-Release (MR / XR) Tablets: 30 mg, 60 mg
11. Visual Pharmacology & Mechanism Diagram (svg-v339-01-adme-12-step-journey)
12. Authoritative References, Regulatory Sources & Editorial Disclaimer
Primary Compendial & Guideline Reference: Indian Pharmacist Desk Reference — Professional Edition 2.7 (2026–27) • Ch 04 [4.6] (p. 47)
Official Verification Portals: Indian Pharmacopoeia Commission (IPC) & National Formulary of India (NFI) • Central Drugs Standard Control Organization (CDSCO) • Ministry of Health & Family Welfare — NLEM 2022 • NCBI Bookshelf / StatPearls Pharmacology Reference • DailyMed (US FDA Official Prescribing Reference)
Last Medically & Pharmaceutically Reviewed: 2026-11-10 • Verification Status: HANDBOOK_SOURCE_CONTENT
Educational & Clinical Disclaimer: This reference profile is published solely for pharmacy education, academic study, and professional clinical reference. It does not substitute for patient-specific clinical judgement, qualified specialist oncology/medical supervision, or official CDSCO/IP prescribing information. Never self-medicate with prescription, Schedule H/H1/X, NDPS, or oncology medicines.
13. Related Reference Monographs, Educational Guides & Visual Concept
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