Corticosteroid Conversion Calculator
Convert a dose between systemic corticosteroids (prednisone, dexamethasone, hydrocortisone and more). Enter a medication and dose to get the equivalent prednisone dose and the full conversion table with potency and half-life.
Convert a Dose Between Systemic Corticosteroids
Corticosteroid Conversion Formula
Where:
- \(D_{\text{entered}}\) — the dose of the medication you are converting from (mg)
- \(B_{\text{entered}}\), \(B_{\text{target}}\) — the base dose of each drug that is equivalent to prednisone 5 mg (hydrocortisone 20 mg, cortisone 25 mg, prednisone/prednisolone 5 mg, methylprednisolone/triamcinolone 4 mg, dexamethasone 0.75 mg, betamethasone 0.6 mg)
- \(D_{\text{prednisone}}\) — the equivalent amount expressed as prednisone (mg)
The formula converts any systemic corticosteroid dose into its anti-inflammatory equivalent in any other drug, using the standard potency table in which each base dose equals prednisone 5 mg.
Corticosteroid Conversion – Calculation Example
Example: a patient takes 30 mg of prednisone per day and needs the equivalent dose of dexamethasone.
\[ D_{\text{prednisone}} = 30 \times \frac{5}{5} = 30 \text{ mg} \]
\[ D_{\text{dexamethasone}} = 30 \times \frac{0.75}{5} = 4.5 \text{ mg} \]
Result: 30 mg prednisone = 30 mg prednisone-equivalent = 4.5 mg dexamethasone once daily. The same conversion also gives 120 mg hydrocortisone or 24 mg methylprednisolone.
How to use the calculator
- Open the Medication drop-down and select the drug you are converting from (for example Prednisone).
- Type the amount into the Dose field in mg. Enter the amount per dose — if the patient takes several doses per day, either enter the daily total or multiply the result by the number of doses.
- Read the Equivalent prednisone dose at the top of the results.
- Check the table Equivalent doses, potency and half-life for the equivalent dose of every drug, its glucocorticoid and mineralocorticoid potency, and its biological half-life. Your entered medication is highlighted.
- Review the Conversion notes and disclaimer before applying any change to therapy.
What is corticosteroid equivalence?
Systemic corticosteroids differ hugely in potency: 0.75 mg of dexamethasone produces roughly the same anti-inflammatory effect as 20 mg of hydrocortisone or 5 mg of prednisone. To compare doses, pharmacology references express every drug in terms of a common standard — usually prednisone 5 mg. The resulting equivalence table lets a clinician translate a prescription from one corticosteroid to another without losing (or doubling) the intended glucocorticoid effect.
Equivalence matters in everyday practice: switching from prednisone to dexamethasone in a patient with cerebral edema, converting hydrocortisone replacement to prednisolone, or comparing doses in research and steroid-safety guidelines, which are usually written in prednisone-equivalent milligrams.
Anti-inflammatory equivalence is only one axis of comparison, though. The result tells you the glucocorticoid effect stays the same, but it says nothing about how long the drug acts (half-life ranges from 8–12 h for hydrocortisone to 36–72 h for betamethasone) or its mineralocorticoid (salt- and water-retaining) activity. Both differences change the clinical outcome of a switch even when the arithmetic is correct.
For the same reason, the daily dosing schedule usually changes with the drug: hydrocortisone and cortisone are given in 2–3 divided doses, intermediate-acting drugs once or twice daily, and dexamethasone or betamethasone once daily or less often because of their long half-lives.
Standard corticosteroid equivalence table
| Medication | Dose equivalent to prednisone 5 mg | Glucocorticoid potency (hydrocortisone = 1) | Mineralocorticoid potency | Half-life |
|---|---|---|---|---|
| Hydrocortisone | 20 mg | 1x | 1x (highest) | Short (8–12 h) |
| Cortisone | 25 mg | 0.8x | 0.8x (high) | Short (8–12 h) |
| Prednisone | 5 mg | 4x | 0.6–0.8x (moderate) | Intermediate (18–36 h) |
| Prednisolone | 5 mg | 4x | 0.6x (moderate) | Intermediate (18–36 h) |
| Methylprednisolone | 4 mg | 5x | about 0.5x (slight) | Intermediate (18–36 h) |
| Triamcinolone | 4 mg | 5x | none | Intermediate (12–36 h) |
| Dexamethasone | 0.75 mg | 25–30x | none | Long (36–54 h) |
| Betamethasone | 0.6 mg | 25–30x | none | Long (36–72 h) |
Assumptions, limitations and clinical tips
- Approximate, population-average ratios. The equivalence figures come from standard pharmacology references (Goodman & Gilman, USP DI) and ignore individual variation, liver disease, and interactions with CYP3A4 inhibitors or inducers. Prednisone itself is a prodrug converted to prednisolone by the liver; in significant hepatic impairment many clinicians prescribe prednisolone directly. Impaired liver function can be scored with the Child-Pugh score.
- Mineralocorticoid effect is not interchangeable. Dexamethasone, betamethasone and triamcinolone retain almost no sodium. Switching a hydrocortisone replacement patient to one of them — or vice versa — is not equivalent replacement therapy, even if the prednisone-equivalent numbers match. potent long-acting drugs are deliberately chosen when salt retention must be avoided.
- Duration of action differs. Equivalent milligrams do not guarantee equivalent duration of HPA-axis suppression; long-acting drugs suppress the hypothalamic-pituitary-adrenal axis markedly longer.
- Route-specific dosing and special protocols. The table applies to enteral and parenteral systemic use. Intra-articular, inhaled, topical and intralesional corticosteroids follow their own dosing, and dexamethasone suppression-test regimens use specific protocols that this equivalence does not describe. Cortisone is often listed as cortisone acetate because the native compound is largely inactive until converted to hydrocortisone by the liver.
- Not medical advice. Verify any conversion against your local formulary and the product labeling before changing a patient's treatment.
For related dose-transformation tasks see the MME opioid conversion calculator, the drug half-life calculator, or the children's acetaminophen dosage calculator.
Frequently Asked Questions
How do I convert corticosteroid doses by hand without a calculator?
Divide the entered dose by the drug's base dose that equals prednisone 5 mg, then multiply by 5. For example, 12 mg dexamethasone equals \( 12 \times \frac{5}{0.75} = 80 \) mg prednisone. To go directly to another drug, multiply the entered dose by the ratio of the two base doses: \( D_{\text{target}} = D_{\text{entered}} \times \frac{B_{\text{target}}}{B_{\text{entered}}} \). A quick check: the more potent drug should always get the smaller number of milligrams.
Are prednisone and prednisolone interchangeable?
In most situations, yes — they are considered equipotent at a 1:1 ratio (5 mg = 5 mg prednisone). Prednisone is a prodrug that the liver converts into the active prednisolone, so in healthy patients the effect is essentially the same. In significant hepatic impairment the conversion can be unreliable, and many clinicians prescribe prednisolone directly instead. Interactions that affect hepatic metabolism can also shift the effective exposure.
What counts as a low, medium, or high corticosteroid dose?
Using prednisone-equivalents, guidelines commonly call low doses under 7.5 mg/day, medium doses 7.5–40 mg/day, and high doses above 40 mg/day; anything over roughly 250 mg/day is often described as mega-dose or pulse therapy. These bands refer to the systemic anti-inflammatory effect only — the risk of side effects such as osteoporosis, hyperglycemia, and infection rises with dose and duration. Always interpret thresholds in the context of the specific indication.
Can I use this conversion for inhaled, topical, or injected steroids?
No, the equivalence table applies only to enteral and parenteral systemic use. Inhaled corticosteroids (fluticasone, budesonide), topical creams, eye drops, nasal sprays, and intra-articular or intralesional injections act locally and follow their own device- or route-specific dosing. Systemic absorption from these routes varies widely, so there is no reliable milligram equivalence to prednisone. For joint injections, the choice depends on the depot formulation, not on the anti-inflammatory potency table.
Does switching to an equivalent dose change the dosing schedule?
Usually yes, because equivalence concerns only the anti-inflammatory effect, not duration of action. Short-acting hydrocortisone and cortisone are typically given in 2–3 divided doses per day to mimic natural cortisol; intermediate-acting prednisone or methylprednisolone once or twice daily; and long-acting dexamethasone or betamethasone once daily or less often. Keeping a long-acting drug on a hydrocortisone schedule can cause excessive HPA-axis suppression, so the frequency must match the half-life.
Can I use this calculator to taper a steroid dose?
Not directly — the calculator converts a dose between drugs but does not design tapering regimens. Tapering depends on the underlying disease, treatment duration, and adrenal recovery, and long-acting drugs such as dexamethasone are generally poor choices for tapering because of prolonged HPA suppression. Long-term patients often need a slow, stepwise reduction rather than a simple conversion. Tapering decisions should always be made with the treating physician.
Why can't I switch a hydrocortisone replacement patient to dexamethasone at the equivalent dose?
Because replacement therapy also depends on mineralocorticoid activity, which the equivalence table does not balance. Hydrocortisone retains sodium strongly, while dexamethasone, betamethasone, and triamcinolone have virtually none — so a numerically 'equivalent' dexamethasone dose would leave an adrenal insufficiency patient without salt and water balance. For adrenal replacement, hydrocortisone (with fludrocortisone if needed) remains the standard. Use the conversion only for anti-inflammatory indications, and confirm replacements with an endocrinologist.