Corticosteroid Conversion Guidelines
Standard Conversion Ratios
- The standard conversion ratio is 5:1, meaning 5 mg of prednisolone equals approximately 1 mg of dexamethasone, as recommended by authoritative guidelines 1, 2, 3
- Prednisolone 20 mg is equivalent to Dexamethasone 4 mg, based on established equivalencies 3
- Prednisolone 60 mg is equivalent to Dexamethasone 10 mg, according to standard conversion ratios 3
Pharmacologic Basis
- 10 mg hydrocortisone is equivalent to 2.0 mg prednisolone and 0.1 mg dexamethasone, establishing dexamethasone as 25 times more potent than hydrocortisone, and prednisolone as 5 times more potent than hydrocortisone 1, 2
- Dexamethasone is approximately 5 times more potent than prednisolone in terms of glucocorticoid activity, as supported by the American College of Clinical Pharmacology 1, 2
Critical Clinical Considerations
- Dexamethasone should be given as a single daily dose rather than divided doses, as recommended by clinical guidelines 3
- A single 8 mg dose of dexamethasone provides glucocorticoid coverage equivalent to 200 mg hydrocortisone for 24 hours, according to the American Society of Anesthesiologists 1, 2
- Dexamethasone has no mineralocorticoid activity, making it inadequate for stress coverage in patients with primary adrenal insufficiency, as stated by the Endocrine Society 1, 2
Practical Conversion Examples
- Prednisolone 40 mg daily is equivalent to Dexamethasone 8 mg daily, based on standard conversion ratios 1, 2, 3
- Prednisolone 1 mg/kg (e.g., 70 mg) is equivalent to Dexamethasone 14 mg, according to clinical guidelines 3
Dexamethasone to Prednisolone Conversion
Pharmacologic Basis for Conversion
- The American Academy of Pediatrics suggests that the relative potency of dexamethasone compared to prednisolone may be even higher than the 5:1 ratio suggests due to its much longer biological half-life, with studies in neonates indicating that low-dose dexamethasone (0.1-0.15 mg/kg/day) may be equivalent to 3-6 mg/kg/day of hydrocortisone 4, 5