# Glucocorticoid dose conversion

Glucocorticoid dose conversion

## Also searched as

- steroid conversion
- glucocorticoid equivalent dose
- hydrocortisone prednisone dexamethasone
- Meikle Tyler 1977
- corticosteroid dose conversion
- prednisone equivalent

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/steroid_conversion`
HTML: https://magentlab.com/docs/steroid-conversion
Markdown: https://magentlab.com/docs/steroid-conversion.md

Not a medical device. Not a diagnosis, dose, or listing recommendation.

## What it computes

Convert a glucocorticoid dose among hydrocortisone, prednisone, and dexamethasone using Meikle 1977 equivalent doses (20 mg : 5 mg : 0.75 mg).

## When to use

When an agent needs a published equivalent dose among those three agents and must not invent a conversion table or add unpublished steroids.

## When not to use

- Not a taper or stress-dose protocol.
- Mineralocorticoid activity is not converted.
- Only hydrocortisone, prednisone, and dexamethasone as published by Meikle 1977.
- magent does not recommend a regimen.

## Formula

```
equivalent_dose_mg = dose_mg * (to_equivalent_mg / from_equivalent_mg); hydrocortisone 20 mg = prednisone 5 mg = dexamethasone 0.75 mg (Meikle 1977)
```

## Citation

[Potency and duration of action of glucocorticoids. Effects of hydrocortisone, prednisone and dexamethasone on human pituitary-adrenal function](https://doi.org/10.1016/0002-9343(77)90233-9)
Meikle AW, Tyler FH
Am J Med. 1977;63(2):200-207
DOI: [10.1016/0002-9343(77)90233-9](https://doi.org/10.1016/0002-9343(77)90233-9)

## Worked example

### 20 mg hydrocortisone to prednisone

Given: `dose_mg=20, from=hydrocortisone, to=prednisone`

1. Meikle 1977 equivalents: hydrocortisone 20 mg, prednisone 5 mg
2. equivalent_dose_mg = 20 * (5 / 20) = 5 mg prednisone


### 20 mg hydrocortisone to dexamethasone

Given: `dose_mg=20, from=hydrocortisone, to=dexamethasone`

1. Meikle 1977 equivalents: hydrocortisone 20 mg, dexamethasone 0.75 mg
2. equivalent_dose_mg = 20 * (0.75 / 20) = 0.75 mg dexamethasone


### Identity 5 mg prednisone

Given: `dose_mg=5, from=prednisone, to=prednisone`

1. Same agent: to_eq / from_eq = 1
2. equivalent_dose_mg = 5 mg prednisone


## Parameters

- `from` (string, required): Source glucocorticoid. hydrocortisone, prednisone, or dexamethasone (Meikle 1977).
- `to` (string, required): Target glucocorticoid. hydrocortisone, prednisone, or dexamethasone (Meikle 1977).
- `dose_mg` (number, required): Dose of the source glucocorticoid in milligrams (0.1-5000).

## Bulk (POST)

POST the same path with a JSON items array. Price is n times the GET unit. Invalid items return HTTP 400 before settlement.

Method: `POST /api/calc/steroid_conversion`
Max items: 25
Price: unit_amount * n (unit 5000 atomic)
Status: PREVIEW

- 1 to 25 items. Each item uses the same keys as the GET query parameters.
- The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
- HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
- Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
- x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request:

```json
{
  "items": [
    {
      "dose_mg": "20",
      "from": "hydrocortisone",
      "to": "prednisone"
    },
    {
      "dose_mg": "20",
      "from": "hydrocortisone",
      "to": "prednisone"
    }
  ]
}
```

Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/steroid-conversion

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/steroid_conversion",
  "items": [
    {
      "from": "hydrocortisone",
      "to": "prednisone",
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Meikle AW, Tyler FH",
        "doi": "10.1016/0002-9343(77)90233-9",
        "id": "meikle-1977",
        "source": "Am J Med. 1977;63(2):200-207",
        "title": "Potency and duration of action of glucocorticoids. Effects of hydrocortisone, prednisone and dexamethasone on human pituitary-adrenal function"
      },
      "formula": "steroid_conversion",
      "formula_expression": "equivalent_dose_mg = dose_mg * (to_equivalent_mg / from_equivalent_mg); hydrocortisone 20 mg = prednisone 5 mg = dexamethasone 0.75 mg (Meikle 1977)",
      "dose_mg": 20.0,
      "equivalent_dose_mg": 5.0,
      "from_equivalent_mg": 20.0,
      "to_equivalent_mg": 5.0
    },
    {
      "from": "hydrocortisone",
      "to": "prednisone",
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Meikle AW, Tyler FH",
        "doi": "10.1016/0002-9343(77)90233-9",
        "id": "meikle-1977",
        "source": "Am J Med. 1977;63(2):200-207",
        "title": "Potency and duration of action of glucocorticoids. Effects of hydrocortisone, prednisone and dexamethasone on human pituitary-adrenal function"
      },
      "formula": "steroid_conversion",
      "formula_expression": "equivalent_dose_mg = dose_mg * (to_equivalent_mg / from_equivalent_mg); hydrocortisone 20 mg = prednisone 5 mg = dexamethasone 0.75 mg (Meikle 1977)",
      "dose_mg": 20.0,
      "equivalent_dose_mg": 5.0,
      "from_equivalent_mg": 20.0,
      "to_equivalent_mg": 5.0
    }
  ]
}
```

## Response fields

- `formula` (string): steroid_conversion
- `formula_expression` (string): Equivalent-dose conversion using Meikle 1977 factors
- `from` (string): Normalized source glucocorticoid
- `to` (string): Normalized target glucocorticoid
- `dose_mg` (number): Input dose in milligrams
- `equivalent_dose_mg` (number): Converted dose in milligrams of the target glucocorticoid
- `from_equivalent_mg` (number): Meikle 1977 equivalent milligrams for the source agent
- `to_equivalent_mg` (number): Meikle 1977 equivalent milligrams for the target agent
- `citation` (object): Meikle and Tyler 1977
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "from": "hydrocortisone",
  "to": "prednisone",
  "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "citation": {
    "authors": "Meikle AW, Tyler FH",
    "doi": "10.1016/0002-9343(77)90233-9",
    "id": "meikle-1977",
    "source": "Am J Med. 1977;63(2):200-207",
    "title": "Potency and duration of action of glucocorticoids. Effects of hydrocortisone, prednisone and dexamethasone on human pituitary-adrenal function"
  },
  "formula": "steroid_conversion",
  "formula_expression": "equivalent_dose_mg = dose_mg * (to_equivalent_mg / from_equivalent_mg); hydrocortisone 20 mg = prednisone 5 mg = dexamethasone 0.75 mg (Meikle 1977)",
  "dose_mg": 20.0,
  "equivalent_dose_mg": 5.0,
  "from_equivalent_mg": 20.0,
  "to_equivalent_mg": 5.0
}
```

## Errors

- HTTP 400 `invalid_steroid`: from and to must be hydrocortisone, prednisone, or dexamethasone. Returned before settlement; you are not charged.
- HTTP 400 `invalid_steroid_dose`: dose_mg must be a number from 0.1 to 5000. Returned before settlement; you are not charged.
- HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
- HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
- HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged.

Shared HTTP 402 and 503: https://magentlab.com/docs/payments

## Related tools

- [Morphine milligram equivalents](https://magentlab.com/docs/mme) — Compute morphine milligram equivalents from a CDC 2022 table opioid and daily dose (or transdermal fentanyl mcg/hr).

## Payment

Required query parameters must be present and valid. Invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s.

- GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall).
- HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote.
- Sign EIP-3009 (scheme exact, assetTransferMethod eip3009) with validBefore = now + accepts[0].maxTimeoutSeconds (600 seconds). That window starts when you sign and must cover wallet confirmation plus CDP verify and settle. Magent retries transient facilitator 429/5xx before answering. Do not send upto or batch-settlement payloads; magent does not offer those schemes.
- Retry the same URL with PAYMENT-SIGNATURE (base64 JSON echoing accepted, payload, and extensions when present).
- Success is HTTP 200 JSON plus PAYMENT-RESPONSE. Settlement happens before the tool runs. HTTP 503 settlement_uncertain or settle_failed: retry the same PAYMENT-SIGNATURE. Mint a new nonce only after a new HTTP 402.

- offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront.

- not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search.
- not offered `batch-settlement`: Not offered. Payment-channel vouchers claimed later in batches. Not the same as POST {items} bulk (that is still exact).

Same-path POST {items} is still scheme exact: one EIP-3009 authorization for n times the GET unit. That is not x402 batch-settlement (payment channels / vouchers).

Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments

Stdio MCP (one process per host): https://magentlab.com/docs/mcp

## Guarantees

- Invalid query parameters return HTTP 400 before settlement. You are not charged.
- Settlement finishes before the tool executes (paymentFlow upfront). Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
- HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
- Execution is timeout-bounded and concurrency-capped.
- Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.