Pharmacy Diabetes

S-9.2 sulfonyluerus-Formulations-Glibenclamide

Name of Medicine

Glibenclamide

Presentation
  • Glibenclamide comes in a 2.5mg and a 5mg tablet.
Key Practice Points
Therapeutic Indications:
  • As an adjunct to healthy eating and physical activity in the treatment of type 2 diabetes. Due to its broad and predictable action, glibenclamide is often used when other forms of management have not been successful.

For the latest PBS indications for glibenclamide please see

https://www.pbs.gov.au/pbs/search?term=glibenclamide&analyse=false&search-type=medicines

Dose:
  • The dose of glibenclamide should be individualised (person centred care) and based on glucose levels.
  • In newly treated individuals with type 2 diabetes, starting dose of glibenclamide is usually 2.5mg with an increase of 2.5mg every 7 days up to a maximum of 15g (sometimes 20mg).
  • Maximum dose of glibenclamide in healthy individuals is 20mg daily.
  • Daily doses of up to 10mg are usually taken at or just after breakfast. Doses exceeding 10mg are more likely to be taken after the evening meal.
  • Due to the fact this medicine can cause hypoglycaemia, it should be given with or soon after breakfast. Regular meals should then be eaten at regular intervals throughout the day if possible.
  • If an individual only has a small breakfast, the tablet should be taken with lunch.
  • The lowest dose that maintains effective glucose levels within range should be considered.
  • Renal impairment – glibenclamide is contraindicated in severe renal impairment.
  • Hepatic impairment – glibenclamide is contraindicated in severe hepatic impairment.
Elderly:
  • Glibenclamide (duration of action 18-24 hours) may have an increased risk of prolonged hypoglycaemia in suspectable individuals. Risk increased in elderly, avoid use if possible.
Contraindications:
  • Known hypersensitivity or allergy to glibenclamide or any of the tablet’s ingredients.
  • Type 1 diabetes
  • Ketoacidosis due to diabetes, or metabolic acidosis
  • Severe renal dysfunction
  • Severe hepatic dysfunction.
  • Pregnancy or lactation
  • Individuals treated with bosentan (used to treat pulmonary hypertension)
Precautions:
    • Any blood glucose level under 4mmol/ L is known as a hypoglycaemic episode when being treated with a sulfonylurea. Counselling how to recognise and treat a hypoglycaemic episode is recommended when starting an individual on a sulfonylurea for the first time. Consideration should also be given to blood glucose monitoring for those who wish to participate.
    • Glucose-6-phosphate Dehydrogenase Deficiency (G6PD)
Treatment of individuals with G6PD-deficiency with sulfonylurea agents can lead to haemolytic anaemia. Since glibenclamide belongs to the chemical class of sulfonylurea drugs, caution should be used in those with G6PD-deficiency and a non-sulfonylurea alternate should be considered.
Adverse Effects:
  • Hypoglycaemia
  • Gastrointestinal reactions Occasional (0.1 to 1%) -nausea, diarrhoea, abdominal pain and vomiting.
  • Dermatologic reactions. Allergic skin reactions (e.g., pruritus, or urticaria). If the reaction continues, the medicine should be stopped. In the event of urticaria, a physician should be consulted.
  • Haematologic reactions. Many reactions have been reported. For further information please consult the full information sheet on glibenclamide.
  • Haemolytic anaemia. Treatment of individuals with glucose-6-phospate dehydrogenase (G6PD) deficiency with sulfonylurea agents can lead to haemolytic anaemia. Since glibenclamide belongs to the class of sulfonylurea agents, caution should be used in those with G6PD-deficiency. An alternative class of medicine should be considered.
Pharmacokinetic Properties-Summary
Absorption:
Glibenclamide is almost completely absorbed after and extensively bound (99%) to serum proteins. Food does not appear to affect the absorption of this medicine.
Distribution:
Multiple dose studies with glibenclamide in people with diabetes suggest no build-up in tissue. The elimination half-life of glibenclamide after intravenous dosage is approximately 2 hours, and 2 to 5 hours after oral administration. Some reports have shown longer half-life of 8 to 10 hours in individuals with diabetes.
Excretion:
Glibenclamide is excreted 50:50 in bile and urine. Renal impairment: Glibenclamide (duration of action 18-24 hours) may have an increased risk of prolonged hypoglycaemia in suspectable individuals. Review is required, as chronic kidney disease (CKD) increases the risk of hypoglycaemia.
More Information

For more detailed information on this product please consult the product information.

https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/PICMI?OpenForm&t=&q=glibenclamide