A single-page opioid Morphine Milligram Equivalent (MME) calculator. Total a patient's daily MME from any mix of home medications, inpatient PRNs, IV drips, PCAs, and pasted EHR administration records, then convert that total to an equivalent dose of a different opioid with suggested scheduled and breakthrough orders, safety alerts, a before/after comparison, and a taper schedule.
Runs entirely in the browser. No backend. No build step. No data leaves the device. Works as a regular website and as an installable PWA you can use offline.
Live version: https://robbie-med.github.io/Mme/
Clinicians (pain medicine, palliative care, anesthesia, hospital medicine, primary care, addiction medicine) who need a fast, transparent scratch-pad for opioid math at the point of care:
- "What's this patient's MME / day?"
- "I need to switch from morphine PO to hydromorphone PO, what dose?"
- "Help me write the actual order: scheduled plus breakthrough."
- "Plan a taper down to ≤50% of current."
- "What's my safety risk at this dose, and should I be co-prescribing naloxone?"
- Open the app (or install it as a PWA).
- Simple view: pick a drug, route, dose, doses-per-day → + Add.
- Repeat for every opioid the patient is on.
- Read the running MME / day total and any safety alerts.
- (Optional) Pick a target opioid plus cross-tolerance reduction to get an equivalent dose, finishable scheduled and breakthrough orders, a before/after comparison, and a taper plan.
For complex cases (inpatient PRNs, IV drips, parsed MAR data, patient context), switch to Complex view.
- Simple: streamlined cards for the everyday case. Add a med, see MME, convert if you want. No clutter.
- Complex: paste-MAR box, Patient Context panel, time-window controls (last 24 / 48 / 72 h or all-normalized-to-24h), the full breakdown table with calculation columns, and a references panel.
- Settings: default view on launch, persistence toggle, equianalgesic table picker (CDC 2022 / GlobalRPh / ASCO), install button, live online/offline cache status, and a confirm-gated Reset.
- Quick-add form with smart unit hints. Fentanyl flips to mcg, the transdermal field becomes Patch rate (mcg/hr), methadone surfaces its tiered-factor note.
- PCA mode: toggle the Add form into a PCA layout for basal rate, demand dose, lockout, and avg demands/day. Effective daily dose is computed and contributes to the same MME total.
- Paste MAR (Complex view): drop in raw EHR text. The parser handles
drug headers, brand names, tall-man lettering, multi-order blocks
(
or-prefixed and unprefixed strength changes), free-text PRN comments, and date / time / dose triplets.
- Headline MME / day updates live as you add or remove entries.
- CDC tiered risk badge: Below threshold (<50), Caution (≥50), High risk (≥90), with the totals card tinted to match.
- Safety alerts below the total: naloxone co-prescription prompt, high-risk review prompt, methadone-specific cautions (QTc, steady state, specialist), meperidine Beers Criteria, tramadol/codeine CYP2D6, fentanyl patch opioid-naïve contraindication. Each carries a citation pointer.
- Patient context amplifications: age band, renal CrCl band, and hepatic Child-Pugh band trigger additional alerts (elderly + meperidine → Beers severe; CKD + morphine → M3G/M6G accumulation; severe hepatic + tramadol → avoid). Context never affects MME math.
- Pick a target (PO / IV / IM / SC / transdermal / chronic PO methadone) and a cross-tolerance reduction (0 / 25 / 33 / 50%).
- Equivalent dose with an explicit calculation breakdown.
- Suggested orders:
- Scheduled: ER BID + IR q4h alternative for PO drugs with ER; q4h scheduled for IR-only; TID for chronic methadone; nearest fentanyl patch size rounded down; continuous mcg/hr for fentanyl IV.
- Breakthrough: 10–20% of new daily, q4h PRN, rounded to clinically reasonable increments (2.5 mg for oxycodone, 0.5 mg for hydromorphone, 5 mg for morphine, etc.).
- Notes: steady-state and ECG for methadone, opioid-tolerance + heat hazard for fentanyl patch, chest-wall rigidity for fentanyl IV.
- Before/after comparison: two-column current-vs-proposed view with each side's total and risk-tier badge plus a Δ from current. Apply this regimen swaps the ledger to the proposed primary entry in one click.
- Taper-schedule generator: stepwise reduction from the proposed regimen. Configurable reduction-per-step (10/15/25/50%), interval (weekly / fortnightly / monthly), and endpoint (≤50% of starting MME / ≤25% / stop). Each row shows the per-drug dose, MME, % of start, and the CDC risk tier crossed into. Copy-to-clipboard yields plaintext with a reassessment reminder.
- Click any MME number to expand a step-by-step derivation: medication, doses in window (with timestamps for parsed entries), normalization step if span > 24 h, factor used, final MME, and a citation that names the active equianalgesic table.
- Click the headline total to see a per-medication breakdown that sums to the displayed value.
A Settings dropdown switches between three preset tables. Each is self-contained: factors, methadone tier breakpoints, label, and citation. All calculations, derivations, conversions, and the EHR-note exporter use the active table.
- Copy URL: encodes the regimen, target, reduction, view, and any
non-default table into the URL hash (via
history.replaceState, so the back button stays clean). Opening the URL restores the full state. - Copy as note: clean plaintext for a progress note. Current regimen, total with risk tier, target conversion plus scheduled and breakthrough orders, safety alerts with citations, table-name trailer, disclaimer.
- Print: a dedicated
@media printstylesheet hides chrome, force-shows derivation panels, and strips colors.
- Settings, patient context, and the medication ledger persist via
localStorage(toggleable). Reset wipes all three keys with a confirm. - Web manifest + service worker precache the entire app shell. First
visit caches it; subsequent loads are served from cache and updated in
the background. On Chromium browsers, an install button appears once
beforeinstallpromptfires.
Frontend-only. ES modules under js/, loaded as <script type="module">.
No bundler; all imports resolve in the browser. localStorage for
persistence; a service worker for offline caching. The medication
ledger is the single source of truth, and a small subscribe/notify
pattern keeps render + hash sync in step without circular imports.
Ledger mutation (addManualEntry / addPCAEntry / addParsedOrders /
removeEntry / clearAll)
│
▼
notify() ────► syncHash() (URL hash)
│
└──────► render() (DOM)
│
├─► mme.js (computeEntryMME per row)
├─► safety.js (risk tier + alerts)
├─► conversion.js (target dose + orders + before/after)
└─► taper.js (taper schedule when conversion picked)
For each entry, computeEntryMME:
- Filter administrations by the active time window (last X hours ending at the latest admin, or all-normalized-to-24h).
- Sum doses, handling unit conversions (g → mg).
- For multi-admin entries spanning > 24 h in "all" mode, scale to a 24-hour rate.
- Look up the factor from the active equianalgesic table.
- Special-case fentanyl transdermal (factor × mcg/hr, latest patch rate) and methadone PO (tiered factor based on total daily mg).
- Multiply for the MME contribution.
#m=morphine|PO|30|1;oxycodone|PO|5|4&t=hydromorphone|PO&rx=25&v=complex&tbl=globalrph
m=: medications asdrug|route|dose|perDay, semicolon-separated.t=: target opioid asdrug|route.rx=: cross-tolerance reduction percent.v=: current view (omitted when equal to the user's default).tbl=: active equianalgesic table (omitted at the default, CDC).
Three tables ship preset. Default is CDC 2022.
The three tables agree on most drugs. The notable difference: ASCO / Practical Pain Management uses a 1:5 hydromorphone PO ratio (factor 5) instead of 1:4 (factor 4).
| Drug | Route | CDC 2022 / GlobalRPh | ASCO / Practical |
|---|---|---|---|
| Morphine | PO | 1 | 1 |
| Morphine | IV / IM / SC | 3 | 3 |
| Hydromorphone | PO | 4 | 5 |
| Hydromorphone | IV / IM / SC | 20 | 25 |
| Oxycodone | PO | 1.5 | 1.5 |
| Oxymorphone | PO | 3 | 3 |
| Oxymorphone | IV / IM / SC | 30 | 30 |
| Hydrocodone | PO | 1 | 1 |
| Codeine | PO | 0.15 | 0.15 |
| Codeine | IV / IM / SC | 0.25 | 0.25 |
| Tramadol | PO | 0.1 | 0.1 |
| Tapentadol | PO | 0.4 | 0.4 |
| Meperidine | PO | 0.1 | 0.1 |
| Meperidine | IV / IM / SC | 0.4 | 0.4 |
| Fentanyl | IV / IM (per mcg) | 0.3 | 0.3 |
| Fentanyl | Transdermal (per mcg/hr-day) | 2.4 | 2.4 |
| Daily methadone dose | CDC 2022 | GlobalRPh | ASCO / Practical |
|---|---|---|---|
| ≤ 20 mg/day | × 4 | × 7 (flat) | × 4 (≤30 mg) |
| 21–40 mg/day | × 8 | × 7 | × 8 (≤90 mg) |
| 41–60 mg/day | × 10 | × 7 | × 8 |
| > 60 mg/day | × 12 | × 7 | × 12 (>90 mg) |
| Total MME | CDC 2022 | GlobalRPh | ASCO / Practical |
|---|---|---|---|
| ≤ 80–99 MME | 4 : 1 | 4 : 1 (≤99) | 4 : 1 (≤90) |
| 100–320 MME | 8 : 1 | 8 : 1 (≤299) | 8 : 1 (≤300) |
| 320–600 MME | 10 : 1 | 12 : 1 (≤499) | 12 : 1 |
| 500–999 MME | 12 : 1 (>600) | 15 : 1 | 12 : 1 |
| 1000–1999 MME | 12 : 1 | 20 : 1 | 12 : 1 |
| ≥ 2000 MME | 12 : 1 | 30 : 1 | 12 : 1 |
python3 -m http.server 8080
# then visit http://localhost:8080Opening index.html directly via file:// will work for most features,
but the service worker requires HTTP(S), so for PWA testing use the
local server.
- Push to
main. - Settings → Pages → Source: Deploy from a branch → main / (root).
- GitHub publishes to
https://<user>.github.io/<repo>/within a minute.
No build step. All assets sit at the repo root (or under js/) with
relative paths.
index.html UI structure
styles.css styling (incl. @media print)
service-worker.js cache-first PWA service worker
manifest.webmanifest PWA manifest
icon-*.png 192 / 512 / maskable / iOS / favicon icons
README.md this file
js/ ES-module sources (no bundler)
├── main.js entry point, init, event wiring
├── drugs.js drug catalog + aliases + route labels
├── tables.js CDC / GlobalRPh / ASCO factor tables
├── settings.js settings + patient context + localStorage
├── ledger.js ledger array, mutations, persistence, subscribe
├── mar-parser.js EHR-paste parser
├── mme.js computeEntryMME, formatters, previewMME
├── safety.js risk tiers + alerts + context amplifications
├── conversion.js target dose, suggested orders, before/after
├── taper.js taper-schedule generator
├── render.js all DOM rendering + derivation panels
├── views.js view state + tab switching
├── form.js quick-add form + PCA mode + context wiring
├── share.js URL hash + copy URL / note + print
├── pwa.js install prompt + offline status
└── util.js escapeHtml
Published equianalgesic ratios are estimates and individual responses vary substantially. Methadone conversions in opioid-tolerant patients should involve a pain or palliative-care specialist; consider baseline and follow-up ECGs for QTc monitoring. Account for residual fentanyl release for 12–24 hours after patch removal and for any long-acting formulations still in the patient's system. Use additional caution in older adults and in renal, hepatic, or pulmonary disease.
This tool is not a substitute for clinical judgement. It does not replace evaluation of pain control, function, withdrawal symptoms, opioid use disorder risk, or relevant guideline review. Patient-specific factors not modeled here (drug–drug interactions, genetic CYP variation, concomitant sedatives, pregnancy, prior opioid exposure pattern) may make the suggested doses inappropriate.