Corticosteroid-Induced Hyperglycemia with Prednisolone

Mechanism of Action

Prednisolone causes hyperglycemia through multiple mechanisms including impaired beta cell insulin secretion, increased total body insulin resistance, and enhanced hepatic gluconeogenesis 1
When taken as a morning dose, prednisolone typically leads to peak hyperglycemia in the late morning and afternoon 1

Prednisolone administered in the morning typically leads to peak hyperglycemia around 8 hours after the dose 1
The hyperglycemic effect is most pronounced during the day and often normalizes overnight, even without treatment 2

The degree of hyperglycemia correlates directly with the prednisolone dose - higher doses cause more significant elevations in blood glucose 1, 3
Patients with pre-existing risk factors for diabetes may experience more pronounced or rapid hyperglycemic effects 4

Blood pressure and serum glucose should be monitored when starting prednisolone therapy 5, 6
For patients on prednisolone who develop hyperglycemia, monitoring should be tailored to the degree of hyperglycemia, with daily monitoring recommended for glucose levels >10 mmol/L 1
Peak hyperglycemic effects should be anticipated 6-9 hours after administration, making afternoon glucose monitoring particularly important 1, 7

Corticosteroid-induced hyperglycemia can occur in 56-86% of hospitalized patients with and without pre-existing diabetes 2

NPH insulin is specifically recommended for steroid-induced hyperglycemia due to its intermediate-acting profile that aligns with the peak hyperglycemic effect of glucocorticoids 7
When adjusting steroid doses, corresponding adjustments to diabetes medications are often necessary to prevent hypoglycemia 1, 2

The American Diabetes Association recommends that short-acting glucocorticoids, such as prednisone, administered once daily in the morning, cause disproportionate hyperglycemia during the day, with blood glucose frequently normalizing overnight without treatment 8
The American Diabetes Association suggests that for once-daily short-acting steroids, NPH insulin is the preferred treatment because its peak action aligns with the steroid's peak hyperglycemic effect, although the specific recommendation is based on 8
Long-acting glucocorticoids, such as dexamethasone, or multiple daily doses require long-acting basal insulin to control fasting blood glucose, as the hyperglycemic effect persists throughout the 24-hour period 8, 9