Glibenclamide Dose Calculator
India · Type 2 Diabetes · Adult Dosing · Hypoglycaemia Risk · Renal Caution · Daonil · Glynase · Betanase
Glibenclamide Dose Calculator
Gliclazide MR 30mg — preferred in elderly, CKD eGFR >15. Less hypoglycaemia, once daily
Glipizide 5mg — shorter acting, fewer active metabolites. Better in elderly
Glimepiride 1mg — once daily, lower hypoglycaemia risk than glibenclamide
All sulphonylureas: cause weight gain and hypoglycaemia
Glibenclamide — Sulphonylurea Comparison for India
| Drug | Starting dose | Max dose | Duration | Elderly safe? | CKD eGFR 30–60 |
|---|---|---|---|---|---|
| Glibenclamide | 2.5 mg OD | 15–20 mg/day | 16–24h | ⛔ Avoid | ⛔ Avoid |
| Gliclazide MR | 30 mg OD | 120 mg/day | 24h | ✓ Preferred | ✓ Use with care |
| Glipizide | 2.5–5 mg OD | 40 mg/day | 12–24h | ⚠️ Use cautiously | ⚠️ Reduce dose |
| Glimepiride | 1 mg OD | 6–8 mg/day | 24h | ⚠️ Use cautiously | ⚠️ Start 1mg |
Glibenclamide — Clinical Guide India
Glibenclamide (also known as glyburide) is a second-generation sulphonylurea that stimulates pancreatic β-cell insulin secretion independently of blood glucose levels. It is one of the cheapest and most widely available antidiabetic drugs in India, listed on the National Essential Medicines List (NEML), and extensively used in primary care settings across government health facilities. While effective at lowering HbA1c (typically 1–2% reduction), glibenclamide carries the highest risk of hypoglycaemia among sulphonylureas due to its long duration of action (16–24 hours) and active metabolites that accumulate in renal impairment.
Elderly patients — why glibenclamide is dangerous
The American Geriatrics Society Beers Criteria, BNF, and most diabetes guidelines explicitly list glibenclamide as inappropriate for use in patients over 65 years. The reasons are well-established: older patients have reduced hepatic clearance of glibenclamide's active metabolites, reduced renal excretion, irregular meal patterns, reduced hypoglycaemia awareness (they may not feel the warning symptoms), and impaired counter-regulatory responses to low blood sugar. Glibenclamide-induced hypoglycaemia in the elderly is often prolonged (lasting 12–24+ hours), recurrent, and can cause falls, fractures, cardiac arrhythmias, and stroke. Any elderly patient presenting with unexplained confusion, falls, or reduced consciousness should have blood glucose checked — glibenclamide-induced hypoglycaemia is a medical emergency requiring IV dextrose and prolonged monitoring (24–48 hours). In elderly patients, gliclazide MR is the preferred sulphonylurea.
Renal impairment — active metabolites accumulate
Unlike gliclazide, glibenclamide has active metabolites that are renally excreted. In CKD (eGFR <60), these metabolites accumulate, amplifying and prolonging insulin secretory activity and dramatically increasing hypoglycaemia risk. Glibenclamide is contraindicated in eGFR <30 and should be avoided (prefer gliclazide MR) in eGFR 30–60. Always check renal function before initiating or continuing glibenclamide. In India, many patients with T2DM have concurrent CKD that is undiagnosed — check eGFR at initiation and annually.
Counselling points for patients
Patients on glibenclamide must be counselled that: they must take the tablet with or immediately before a meal — taking it and then skipping a meal is the most common cause of hypoglycaemia. Alcohol significantly increases the hypoglycaemia risk. They should carry glucose tablets or sugar sachets at all times. They should recognise hypoglycaemia symptoms (sweating, trembling, palpitations, confusion, dizziness) and know how to treat mild hypoglycaemia (15–20g fast-acting carbohydrate). Driving or operating machinery should be done cautiously when starting the medication or when hypoglycaemia episodes have occurred.