FACE DROPS Lyme vs Bell palsy

FACE DROPS

Sum the seven McEntire 2025 FACE DROPS criteria from caller-assigned flags and return whether the total favors Bell palsy (score ≤4), is indeterminate (5–6), or favors Lyme disease-associated facial palsy (score ≥7).

LIVE $0.005 USDC GET /api/calc/face_drops

Markdown: /docs/face-drops.md · Canonical: https://magentlab.com/docs/face-drops

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

What it computes

When to use

When an agent already has the seven McEntire 2025 FACE DROPS items assigned as present or absent and needs the published −1 to 28 total and the paper's ≤4 / 5–6 / ≥7 classification, not a Lyme test, serology order, facial examination, or stroke mimic score.

When not to use

Not a medical device. Not a Lyme test and not a diagnosis of Bell palsy or Lyme disease-associated facial palsy. magent does not examine the face or order serology.
Each item is a caller-assigned boolean. Scores ≤4 predicted Bell palsy and scores ≥7 predicted Lyme disease-associated facial palsy in McEntire 2025; 5–6 is indeterminate. magent does not invent extra cutoffs or probabilities.
This is the McEntire 2025 seven-criterion FACE DROPS instrument only, not the 2024 abstract FACE DROP weights and not a stroke FACE-DROPS mimic score.

Formula

FACE DROPS = 8*fever + 6*aches + 3*cephalalgia + 4*exhaustion + 4*dermatomal_or_radicular - 1*otalgia_or_postauricular_pain + 3*stiff_neck; range -1 to 28; favors_bell_palsy iff score <= 4; indeterminate iff 5-6; favors_ldfp iff score >= 7 (McEntire 2025)

Citation

Title: FACE DROPS: A Clinical Risk Assessment Tool for Differentiation of Acute Lyme Disease-Associated Facial Palsy From Bell Palsy
Authors: McEntire CRS, Chung SY, Chang B, Barrera KJ, Zhao Y, Joseph JW, Wormser GP, Jowett N, Chwalisz BK
Source: Neurol Clin Pract. 2025;15(3):e200476
DOI: 10.1212/CPJ.0000000000200476

Worked example

All seven flags false

Given: aches=falsecephalalgia=falsedermatomal_or_radicular=falseexhaustion=falsefever=falseotalgia_or_postauricular_pain=falsestiff_neck=false

Fever, aches, cephalalgia, exhaustion, dermatomal or radicular pattern, otalgia or postauricular pain, and stiff neck false → 0 each
Score = 0 (max 28); classification favors_bell_palsy because score ≤4

Fever only

Given: aches=falsecephalalgia=falsedermatomal_or_radicular=falseexhaustion=falsefever=trueotalgia_or_postauricular_pain=falsestiff_neck=false

Fever true → +8; remaining flags false → 0
Score = 8 (max 28); classification favors_ldfp because score ≥7

Otalgia or postauricular pain only

Given: aches=falsecephalalgia=falsedermatomal_or_radicular=falseexhaustion=falsefever=falseotalgia_or_postauricular_pain=truestiff_neck=false

Otalgia or postauricular pain true → −1; remaining flags false → 0
Score = −1 (max 28); classification favors_bell_palsy because score ≤4

Also searched as

FACE DROPS
Lyme facial palsy
Bell palsy vs Lyme
McEntire FACE DROPS
LDFP score
Lyme disease-associated facial palsy
nuchal rigidity facial palsy
acute facial palsy Lyme

Try

Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.

/api/calc/face_drops?fever=false&aches=false&cephalalgia=false&exhaustion=false&dermatomal_or_radicular=false&otalgia_or_postauricular_pain=false&stiff_neck=false

Full URL: https://api.magentlab.com/api/calc/face_drops?fever=false&aches=false&cephalalgia=false&exhaustion=false&dermatomal_or_radicular=false&otalgia_or_postauricular_pain=false&stiff_neck=false

Call

Expect HTTP 402 until you retry with PAYMENT-SIGNATURE. Incomplete query params return HTTP 400 before any quote or charge.

curl -i -H "Accept: application/json" "https://api.magentlab.com/api/calc/face_drops?fever=false&aches=false&cephalalgia=false&exhaustion=false&dermatomal_or_radicular=false&otalgia_or_postauricular_pain=false&stiff_neck=false"

Parameters

Name	Type	Required	Description
`fever`	boolean	required	Fever (McEntire 2025, +8 if true). true or false as assigned by the caller. magent does not examine the patient or measure temperature.
`aches`	boolean	required	Arthralgia or myalgia (McEntire 2025, +6 if true). true or false as assigned by the caller. magent does not examine the patient.
`cephalalgia`	boolean	required	Headache / cephalalgia (McEntire 2025, +3 if true). true or false as assigned by the caller. magent does not examine the patient.
`exhaustion`	boolean	required	Unusual fatigue / exhaustion (McEntire 2025, +4 if true). true or false as assigned by the caller. magent does not examine the patient.
`dermatomal_or_radicular`	boolean	required	Dermatomal or radicular pattern (transverse myelitis or radiculitis) (McEntire 2025, +4 if true). true or false as assigned by the caller. magent does not examine the patient.
`otalgia_or_postauricular_pain`	boolean	required	Otalgia or postauricular pain (McEntire 2025, −1 if true). true or false as assigned by the caller. magent does not examine the patient.
`stiff_neck`	boolean	required	Stiff neck / nuchal rigidity (McEntire 2025, +3 if true). true or false as assigned by the caller. magent does not examine the patient.

Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

POST /api/calc/face_drops Max 25 unit_amount + extra_item_amount * (n - 1) extra $0.002 PREVIEW

1 to 25 items. Each item uses the same keys as the GET query parameters.
POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
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 (fixture)

{
  "items": [
    {
      "aches": "false",
      "cephalalgia": "false",
      "dermatomal_or_radicular": "false",
      "exhaustion": "false",
      "fever": "false",
      "otalgia_or_postauricular_pain": "false",
      "stiff_neck": "false"
    },
    {
      "aches": "false",
      "cephalalgia": "false",
      "dermatomal_or_radicular": "false",
      "exhaustion": "false",
      "fever": "false",
      "otalgia_or_postauricular_pain": "false",
      "stiff_neck": "false"
    }
  ]
}

Open bulk paywall →

Opens a two-item fixture on the API host. Unpaid browsers get the same MetaMask paywall as GET; Pay retries POST with those items.

Example 200 (fixture)

{
  "count": 2,
  "path": "/api/calc/face_drops",
  "items": [
    {
      "components": [
        {
          "factor": "fever",
          "points": 0,
          "present": false
        },
        {
          "factor": "aches",
          "points": 0,
          "present": false
        },
        {
          "factor": "cephalalgia",
          "points": 0,
          "present": false
        },
        {
          "factor": "exhaustion",
          "points": 0,
          "present": false
        },
        {
          "factor": "dermatomal_or_radicular",
          "points": 0,
          "present": false
        },
        {
          "factor": "otalgia_or_postauricular_pain",
          "points": 0,
          "present": false
        },
        {
          "factor": "stiff_neck",
          "points": 0,
          "present": false
        }
      ],
      "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": "McEntire CRS, Chung SY, Chang B, Barrera KJ, Zhao Y, Joseph JW, Wormser GP, Jowett N, Chwalisz BK",
        "doi": "10.1212/CPJ.0000000000200476",
        "id": "mcentire-2025",
        "pmid": "40290705",
        "source": "Neurol Clin Pract. 2025;15(3):e200476",
        "title": "FACE DROPS: A Clinical Risk Assessment Tool for Differentiation of Acute Lyme Disease-Associated Facial Palsy From Bell Palsy"
      },
      "formula": "face_drops",
      "formula_expression": "FACE DROPS = 8*fever + 6*aches + 3*cephalalgia + 4*exhaustion + 4*dermatomal_or_radicular - 1*otalgia_or_postauricular_pain + 3*stiff_neck; range -1 to 28; favors_bell_palsy iff score <= 4; indeterminate iff 5-6; favors_ldfp iff score >= 7 (McEntire 2025)",
      "max_score": 28,
      "score": 0,
      "classification": "favors_bell_palsy"
    },
    {
      "components": [
        {
          "factor": "fever",
          "points": 0,
          "present": false
        },
        {
          "factor": "aches",
          "points": 0,
          "present": false
        },
        {
          "factor": "cephalalgia",
          "points": 0,
          "present": false
        },
        {
          "factor": "exhaustion",
          "points": 0,
          "present": false
        },
        {
          "factor": "dermatomal_or_radicular",
          "points": 0,
          "present": false
        },
        {
          "factor": "otalgia_or_postauricular_pain",
          "points": 0,
          "present": false
        },
        {
          "factor": "stiff_neck",
          "points": 0,
          "present": false
        }
      ],
      "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": "McEntire CRS, Chung SY, Chang B, Barrera KJ, Zhao Y, Joseph JW, Wormser GP, Jowett N, Chwalisz BK",
        "doi": "10.1212/CPJ.0000000000200476",
        "id": "mcentire-2025",
        "pmid": "40290705",
        "source": "Neurol Clin Pract. 2025;15(3):e200476",
        "title": "FACE DROPS: A Clinical Risk Assessment Tool for Differentiation of Acute Lyme Disease-Associated Facial Palsy From Bell Palsy"
      },
      "formula": "face_drops",
      "formula_expression": "FACE DROPS = 8*fever + 6*aches + 3*cephalalgia + 4*exhaustion + 4*dermatomal_or_radicular - 1*otalgia_or_postauricular_pain + 3*stiff_neck; range -1 to 28; favors_bell_palsy iff score <= 4; indeterminate iff 5-6; favors_ldfp iff score >= 7 (McEntire 2025)",
      "max_score": 28,
      "score": 0,
      "classification": "favors_bell_palsy"
    }
  ]
}

Response

Field	Type	Description
`formula`	string	face_drops
`formula_expression`	string	Exact expression used
`score`	integer	FACE DROPS points -1 to 28 (McEntire 2025)
`max_score`	integer	28
`classification`	string	favors_bell_palsy if score ≤4, indeterminate if 5–6, favors_ldfp if score ≥7 (McEntire 2025). Not a diagnosis.
`components`	array	Per-criterion points
`citation`	object	McEntire et al. Neurol Clin Pract 2025 citation
`disclaimer`	string	Not-a-device notice

Example JSON

Machine form of the same example. Frozen fixture. Not a live lookup.

{
  "components": [
    {
      "factor": "fever",
      "points": 0,
      "present": false
    },
    {
      "factor": "aches",
      "points": 0,
      "present": false
    },
    {
      "factor": "cephalalgia",
      "points": 0,
      "present": false
    },
    {
      "factor": "exhaustion",
      "points": 0,
      "present": false
    },
    {
      "factor": "dermatomal_or_radicular",
      "points": 0,
      "present": false
    },
    {
      "factor": "otalgia_or_postauricular_pain",
      "points": 0,
      "present": false
    },
    {
      "factor": "stiff_neck",
      "points": 0,
      "present": false
    }
  ],
  "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": "McEntire CRS, Chung SY, Chang B, Barrera KJ, Zhao Y, Joseph JW, Wormser GP, Jowett N, Chwalisz BK",
    "doi": "10.1212/CPJ.0000000000200476",
    "id": "mcentire-2025",
    "pmid": "40290705",
    "source": "Neurol Clin Pract. 2025;15(3):e200476",
    "title": "FACE DROPS: A Clinical Risk Assessment Tool for Differentiation of Acute Lyme Disease-Associated Facial Palsy From Bell Palsy"
  },
  "formula": "face_drops",
  "formula_expression": "FACE DROPS = 8*fever + 6*aches + 3*cephalalgia + 4*exhaustion + 4*dermatomal_or_radicular - 1*otalgia_or_postauricular_pain + 3*stiff_neck; range -1 to 28; favors_bell_palsy iff score <= 4; indeterminate iff 5-6; favors_ldfp iff score >= 7 (McEntire 2025)",
  "max_score": 28,
  "score": 0,
  "classification": "favors_bell_palsy"
}

Client errors (HTTP 400)

Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.

HTTP	Code	When
400	`invalid_flag`	boolean clinical flags must be true or false Returned before settlement; you are not charged.
400	`invalid_items`	POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
400	`invalid_item_count`	items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
400	`invalid_item`	each items entry must be a JSON object Returned before settlement; you are not charged.

Related tools

HINTS — Apply the Kattah 2009 three-step HINTS exam (Head-Impulse, Nystagmus, Test-of-Skew) from three caller-assigned flags and return whether any dangerous central sign is present.
ROSIER — Sum the seven Nor 2005 ROSIER items from caller-assigned flags and return whether the score is greater than 0 (stroke more likely).
FAST-ED — Sum Lima 2016 Field Assessment Stroke Triage for Emergency Destination (FAST-ED) points from caller-assigned facial palsy, arm weakness, speech, eye deviation, and neglect, and return whether the total suggests large-vessel occlusion (score ≥4) plus the published LVO-rate band.

Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, 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. Unpaid valid requests return HTTP 402 with a base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote: retry the same PAYMENT-SIGNATURE. Full handshake and shared payment errors: Payments. Stdio MCP: /docs/mcp.

Guarantees

HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. 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.