Drug-drug interactions · ships on RapidAPI
The drop-in RxNav replacement.
The NLM RxNav Drug-Drug Interaction API shut down Jan 2, 2024. Mortar fills the gap: send a list of drug names, get pairwise interactions back in the same JSON shape — with RxNorm normalization built in.
Why Mortar
Drop-in compatible
Responses mirror RxNav's findInteractionsFromList — point your old parser at Mortar and go.
RxNorm normalization
Generic names, brand names (Zocor → simvastatin), and even typos resolve to canonical RxCUIs automatically.
Commercial-use license
Built only from public, commercially-usable sources. No DrugBank, no NonCommercial data.
Optional AI explanations
Flip explain:true for a plain-language summary of each interaction, cached for instant repeat calls.
Quick start
curl -X POST "https://mortar-drug-interaction-api3.p.rapidapi.com/interactions" \
-H "X-RapidAPI-Key: YOUR_RAPIDAPI_KEY" \
-H "X-RapidAPI-Host: mortar-drug-interaction-api3.p.rapidapi.com" \
-H "content-type: application/json" \
-d '{ "drugs": ["warfarin", "aspirin", "simvastatin"] }'Each interaction comes back grouped by source with severity and description, plus resolved / unresolved diagnostics. Calls go through the RapidAPI gateway.
Endpoints
| Method | Path | Description |
|---|---|---|
| POST | /interactions | Pairwise interactions for a list of drugs. |
| GET | /v1/manifest | Machine-readable capability manifest (for AI agents). |
| GET | /openapi.yaml | OpenAPI 3.0 spec. |
| GET | /health | Liveness + dataset readiness. |
Plans
| Plan | Price | Requests / month |
|---|---|---|
| Basic | Free | 2,500 |
| Pro | $12 / mo | 60,000 |
| Ultra | $59 / mo | 750,000 |
| Mega | $199 / mo | 7,000,000 |
Every plan includes RxNorm normalization, AI explanations, the commercial-use license, and the NLM-compatible response shape. Quotas and billing are managed by RapidAPI.
FAQ
Is the NLM RxNav Drug Interaction API still available?
No. The U.S. National Library of Medicine discontinued the RxNav Drug-Drug Interaction API (findDrugInteractions and findInteractionsFromList) on January 2, 2024. Mortar is a drop-in replacement that returns interactions in the same JSON shape.
What can I use to replace findInteractionsFromList?
Mortar mirrors RxNav's findInteractionsFromList response (fullInteractionTypeGroup → fullInteractionType → interactionPair with severity and description). Point your existing parser at Mortar and migrate with mostly copy-paste changes.
Does Mortar normalize brand names and misspelled drug names?
Yes. RxNorm normalization is built in, so generic names, brand names (Zocor → simvastatin), and common typos (asprin → aspirin) all resolve to canonical RxNorm RxCUIs automatically.
Can I use Mortar in a commercial product?
Yes. Mortar is built only from public, commercially-usable sources — the ONCHigh DDI list and openFDA labeling, normalized via NLM RxNorm/RxNav. No DrugBank or NonCommercial DDInter data.
Is Mortar a substitute for medical advice?
No. Mortar is for educational and informational use only. It is not clinical decision support and not a substitute for a pharmacist or physician. It never labels a combination "safe" or "unsafe."