- Sulfonylureas increase insulin production and may decrease insulin resistance.
- The most significant side effect of all sulfonylureas is hypoglycaemia (defined as a blood glucose level below 4 mmol/L). Glibenclamide (duration of action 18-24 hours) and glimepiride (duration of action 24 hours but also has active metabolites) may have an increased risk of prolonged hypoglycaemia especially in individuals that may be vulnerable. This includes the elderly or in individuals with renal dysfunction.
- This might also be true of modified release gliclazide (duration of action 16 to 24 hours). Gliclazide immediate release (duration of action 12 to 16 hours) has been shown to have fewer hypoglycaemic episodes that all other sulfonylureas Glipizide (duration of action 6-8 hours) may be a reasonable choice for vulnerable individuals.
- Any blood glucose level under 4mmol/ L is known as a hypoglycaemic episode when being treated with a sulfonylurea.
- Blood glucose level under 4mmol/L must be treated appropriately.
- Sulfonylureas should be taken with food to reduce the chance of hypoglycaemia.
- Diabetes MedsCheck with counselling on how to recognise and treat hypoglycaemic episodes.
- Referral for blood glucose monitoring.
- All sulfonylureas should be taken with food to reduce the risk of hypoglycaemia.
- Sulfonylureas can be given once or twice a day depending on the duration of action.
- With alcohol, ensure adequate amounts of food (in particular carbohydrates) are eaten before going to bed to protect against nocturnal hypoglycaemia.
- It should be noted that a cross reactivity exists between sulfonylureas and sulphonamides. This often presents as skin eruptions or urticaria.
- Consider ceasing medicine with referral to healthcare team.
Where a prescribed sulfonylurea is not working to lower blood glucose levels, changing the prescription to another sulfonylurea, or increasing the dose may not work. Substitution with, or addition of, another sulfonylurea may not always be effective in lowering glucose levels. Addition of a medicine from another class may have a greater benefit
- Diabetes MedsCheck with referred to healthcare team for further intervention.