Glibenclamide
A sulfonylurea for type 2 diabetes whose hypoglycemia risk is higher in older people and in kidney or liver disease.
Also called glyburide (US name).
Drug card
- Class
- Sulfonylurea
- How it works
- Closing KATP channels on beta cells, so the pancreas releases insulin
- Used for
- Type 2 diabetes
- Known for
- Low blood sugar (hypoglycemia), sometimes prolonged
- Its name
- gli- means a glucose-lowering drug, often a sulfonylurea
Study it as a flashcard, and it comes back before you forget it.
Mechanism of action
How does glibenclamide work?
Glibenclamide binds SUR1 and closes KATP channels on beta cells; calcium entry then triggers insulin release. Its long-term glucose lowering may also involve actions outside the pancreas that are not fully understood. The liver turns it into two weakly active hydroxy metabolites, and it mildly increases free water clearance by the kidney.
Like other sulfonylureas: Sulfonylureas bind the SUR1 subunit of ATP-sensitive potassium (KATP) channels on pancreatic beta cells and close them. Calcium then enters through voltage-gated channels and triggers the release of stored insulin. They need working beta cells, so they do not help type 1 diabetes, and a missed meal while taking them can cause hypoglycemia.
Uses
What is glibenclamide used for?
- Type 2 diabetes
Side effects
Side effects of glibenclamide
- Low blood sugar (hypoglycemia), sometimes prolongedKnown forSerious
- Nausea, fullness and heartburn
- Rash, itching or hives
- Cholestatic jaundice, rarely progressing to liver failureSerious
- Raised liver enzymes and hepatitisSerious
- Blood disorders such as agranulocytosis, aplastic anemiaSerious
- Hemolytic anemia, especially with G6PD deficiencySerious
- Low sodium (hyponatremia)Serious
- Sun sensitivity (photosensitivity)
- Blurred vision as glucose levels change
- Flushing with alcohol (disulfiram-like), very rare
- Possible rise in cardiovascular deaths (label warning)Serious
Known for marks what an exam expects you to know it for.
Watch for
Cautions and what sets it apart
- Contraindicated in type 1 diabetes, in diabetic ketoacidosis and with bosentan (liver enzyme rises).
- Older, frail or malnourished people and those with kidney or liver disease are prone to serious hypoglycemia.
- NSAIDs, sulfonamides, beta blockers and other highly protein-bound drugs can strengthen its effect.
- If used in pregnancy, stop it at least two weeks before delivery: newborns can have prolonged hypoglycemia.
Good to know: Called glyburide in the US. Hypoglycemia can be hard to spot in older people and in those taking beta blockers.
Remember it
A way to remember it
Sulfonylureas squeeze insulin out of the beta cell: skip a meal and you get a hypo, and the extra insulin adds weight.
They close KATP channels so beta cells release insulin. Hypoglycemia, worst when meals are missed, and weight gain are the two classic side effects.
Written for biofideX
Its name
gli- means glucose-lowering drug, often a sulfonylurea
At the start of a name it mostly marks sulfonylureas: gliclazide, glimepiride, glibenclamide (US glyburide). The same letters sit inside -gliptin, -gliflozin and -glitazone.
- Every drug name stem
Its class
Sulfonylureas
Other sulfonylureas with a card:
Easily mixed up with DPP-4 inhibitors and SGLT2 inhibitors.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
For learning pharmacology, not for treatment decisions: no doses are given, and a prescriber, pharmacist or the product's own label is the word on any one patient. Spotted a mistake? Tell us and we'll correct it.
Diabetes
Glibenclamide is one of 14 drugs practiced together here: their classes, how they work, what they treat and what they're known for.
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