Adjusting insulin

Patients with type 2 diabetes being treated with insulin should be encouraged to seek medical assistance early in the course of an acute illness so insulin dosage can be adjusted if necessary. More frequent monitoring of blood glucose concentration is required and basal insulin requirements are likely to increase.

If the patient’s acute illness is not accompanied by nausea or vomiting, and their blood glucose concentrations are more than 12 mmol/L without any episodes of hypoglycaemia, they should give their usual dose of insulin plus 10 to 20% of that dose (110 to 120% of the usual insulin dose) while their blood glucose concentration remains high.

For patients using basal insulin alone, short-term rapid-acting insulin (bolus doses) may be needed to manage acute hyperglycaemia (see Adding bolus insulin to a basal insulin regimen for adults with type 2 diabetes).

For patients using a mixed insulin regimen (fixed-dose combination [biphasic premixed] insulin), a short-term switch to a basal insulin plus bolus doses of rapid-acting insulin before one or all meals may be required because fixed-dose combination doses can be difficult to adjust for a patient with poor oral intake.