How long can oral corticosteroids (CS) continue to elevate a patient's blood glucose levels, causing hyperglycemia?

From the Guidelines

Oral corticosteroids can continue to elevate a patient's blood glucose levels for up to several days after discontinuation, with the effect typically peaking in the evening and returning to normal or near-normal levels overnight, as observed in patients treated with daily prednisone or prednisolone 1. The duration and severity of hyperglycemia depend on several factors, including the specific steroid used, dosage, and duration of treatment.

• Prednisone, prednisolone, and dexamethasone are common oral steroids that affect glucose metabolism.
• Higher doses and longer treatment periods typically result in more prolonged hyperglycemic effects.
• Patients with pre-existing diabetes or risk factors for diabetes are particularly susceptible to these effects. Steroids cause hyperglycemia by increasing insulin resistance, enhancing gluconeogenesis in the liver, and decreasing glucose uptake in peripheral tissues 1. For patients on steroid therapy, blood glucose monitoring is recommended, especially during the first few days of treatment and after discontinuation 1. Those with diabetes may need temporary adjustments to their diabetes medications during and shortly after steroid therapy. The hyperglycemic effect typically follows a diurnal pattern with higher glucose levels later in the day when steroids are taken in the morning, as supported by the most recent study in 2025 1. Key considerations for managing hyperglycemia in patients on oral corticosteroids include:
• Administering intermediate-acting insulin concomitantly with steroids for once- or twice-daily regimens.
• Using long-acting basal insulin for long-acting glucocorticoids or multidose regimens.
• Adjusting insulin doses based on anticipated changes in glucocorticoid dosing and point-of-care glucose test results.

From the Research

Duration of Hyperglycemia

• The duration of hyperglycemia caused by oral corticosteroids (CS) can vary, but studies suggest that it can last for several days to a week after injection or treatment 2, 3, 4.
• A systematic review of intra-articular steroid injections in patients with diabetes found that post-injection hyperglycemia occurred within 24 to 72 hours in many patients, and patients should be advised to monitor their blood glucose levels for up to a week after injection 2.
• A study on the effect of short-term, medium-dose prednisone on 24-hour metabolic patterns found that hyperglycemia occurred predominantly between midday and midnight, and effective treatment should target both rapid onset relative insulin deficiency and a less than 24-hour total duration of effect 3.
• Another study found that the mean blood glucose concentration was greater with dexamethasone and methylprednisolone compared to hydrocortisone and prednisolone, and more vigorous monitoring and intervention are suggested in adult inpatients receiving corticosteroids, particularly dexamethasone and methylprednisolone 5.

Factors Affecting Hyperglycemia

• The type and dose of corticosteroid used can affect the degree of hyperglycemia, with dexamethasone and methylprednisolone associated with greater hyperglycemia compared to hydrocortisone and prednisolone 5.
• The pattern of hyperglycemia throughout the day can also vary, with one study finding that hyperglycemia occurred predominantly between midday and midnight 3.
• The duration of treatment with corticosteroids can also impact the degree of hyperglycemia, with one study finding that the prednisolone dose was reduced and the insulin dose was increased over time in patients treated for 3 days 4.

Monitoring and Management

• Patients with diabetes should be advised to regularly monitor their blood glucose levels for up to a week after injection or treatment with corticosteroids 2.
• More vigorous monitoring and intervention are suggested in adult inpatients receiving corticosteroids, particularly dexamethasone and methylprednisolone 5.
• Effective treatment of prednisone-induced hyperglycemia should target both rapid onset relative insulin deficiency and a less than 24-hour total duration of effect 3.