What is the equivalent dose of different steroids, such as prednisone (corticosteroid), hydrocortisone (corticosteroid), prednisolone (corticosteroid), and methylprednisolone (corticosteroid)?

Corticosteroid Equivalent Dosing

The standard equivalent doses are: hydrocortisone 20 mg = prednisolone/prednisone 5 mg = methylprednisolone 4 mg = dexamethasone 0.75 mg. 1, 2, 3

Core Conversion Ratios

Relative Potency to Hydrocortisone

• Hydrocortisone: 1x (baseline reference) 1
• Prednisolone/Prednisone: 4x more potent than hydrocortisone 2
• Methylprednisolone: 5x more potent than hydrocortisone 2
• Dexamethasone: 25x more potent than hydrocortisone 1, 2

Direct Conversion Table

• Hydrocortisone 20 mg = Prednisolone 5 mg 1
• Prednisone 5 mg = Methylprednisolone 4 mg 1, 4
• Prednisone 5 mg = Dexamethasone 0.75-1 mg 2, 3
• Prednisone 20 mg = Dexamethasone 4 mg 2
• Prednisone 60 mg = Methylprednisolone 48 mg 2
• Prednisone 60 mg = Dexamethasone 10 mg 2

FDA-Approved Equivalencies

The FDA drug label for prednisolone specifies that 15 mg prednisolone base equals: 3

• Cortisone 75 mg
• Hydrocortisone 60 mg
• Prednisone 15 mg
• Methylprednisolone 12 mg
• Triamcinolone 12 mg
• Dexamethasone 2.25 mg
• Betamethasone 2.25 mg

Clinical Application Guidelines

Perioperative Dosing

For patients on chronic corticosteroids undergoing surgery, continue equivalent dosing intravenously until oral intake resumes. 1 Specifically:

• Prednisolone 5 mg oral = Hydrocortisone 20 mg IV 1
• No evidence supports routine stress-dose supplementation beyond therapeutic replacement 1
• Dexamethasone 8 mg IV provides equivalent coverage to hydrocortisone 200 mg for 24 hours 1

Critical caveat: Dexamethasone lacks mineralocorticoid activity and is inadequate for primary adrenal insufficiency stress coverage 1

Acute Graft-versus-Host Disease

Use methylprednisolone 1-2 mg/kg/day (or prednisone dose equivalent) for grade 2-4 acute GVHD. 1 The conversion is straightforward:

• Methylprednisolone dose = Prednisone dose (essentially 1:1 for practical purposes) 1
• No benefit to escalating methylprednisolone above 2 mg/kg/day 1

Inflammatory Bowel Disease Surgery

Patients on corticosteroids at time of IBD surgery should receive IV hydrocortisone in equivalent dosage until oral prednisolone can resume. 1 The conversion:

• Prednisolone 5 mg oral = Hydrocortisone 20 mg IV 1
• Methylprednisolone 4 mg = Prednisolone 5 mg 1

Immune Checkpoint Inhibitor Toxicities

For grade 2+ pneumonitis, use prednisone 1 mg/kg/day or IV methylprednisolone equivalent. 1 The practical conversion is 1:1 between oral prednisone and IV methylprednisolone for this indication 1

Important Pharmacokinetic Considerations

Bioavailability and Absorption

• All oral corticosteroids (hydrocortisone, prednisolone, methylprednisolone, dexamethasone) have excellent oral bioavailability and rapid absorption 1
• Prednisolone shows dose-dependent pharmacokinetics with saturable protein binding at higher doses, making dose predictions less reliable 5
• Methylprednisolone demonstrates linear, predictable pharmacokinetics without dose or time dependency 5

Half-Life and Duration

• Hydrocortisone plasma elimination half-life: approximately 90 minutes 1
• Half-life may be shorter with CYP3A4 inducers or hyperthyroidism, longer in critically ill patients 1
• Dexamethasone provides longer duration of action despite similar absorption 1

Route-Specific Considerations

IV infusion is superior to IM injection for maintaining physiologic cortisol concentrations during stress. 1 However, IM administration remains safe and effective when IV access is impractical 1

Critical warning: The dose equivalencies listed apply only to oral or IV administration—intramuscular or intra-articular injection significantly alters relative potencies 3

Mineralocorticoid Activity

Hydrocortisone possesses mineralocorticoid activity; synthetic corticosteroids (prednisolone, methylprednisolone, dexamethasone) have progressively less. 6 Specifically:

• Methylprednisolone causes significantly less hypokalemia than hydrocortisone at equivalent anti-inflammatory doses 6
• Dexamethasone has no mineralocorticoid activity 1
• For primary adrenal insufficiency, hydrocortisone or addition of fludrocortisone is required 1

Dosing Pitfalls to Avoid

Common Errors

• Do not confuse methylprednisolone with methylprednisone—they are different compounds 2
• Conversions assume normal hepatic function; adjust for CYP3A4 inducers or inhibitors 1
• Higher doses of prednisolone (>40 mg) show non-linear kinetics due to protein binding saturation 5

Safety Monitoring

• Pneumocystis jirovecii prophylaxis is indicated for patients receiving ≥20 mg prednisone equivalent for ≥4 weeks 1, 7
• Consider GI prophylaxis with proton pump inhibitors for patients on systemic corticosteroids 1
• Calcium and vitamin D supplementation recommended with prolonged steroid use 1