N-way
Up to 50 drugs, one call
Send 2–50 drugs; the API generates every unique pair and checks each against the interactions table. No client-side pairing, no quadratic round-trips.
Drug Database
Capability · Interaction checks
N-way interaction checks, one POST.
Send 2–50 drugs by ATC, ID or market identifier and get every interacting pair back with a graded severity, mechanism and recommendation.
POST /api/v1/interactions/check
What you get
Built for production drug data
One POST checks a whole medication list. The API resolves every drug you send — by ATC code, internal ID or market identifier (Pharmacode, GTIN, NDC, PZN, CIP13) — down to its WHO ATC code, builds every unique pair, and returns the interactions it finds with a graded severity, the mechanism and a clinical recommendation.
Matching is ATC-based, so it is jurisdiction-agnostic: a Swiss Pharmacode and a US NDC for the same molecule collapse to the same ATC and interact identically.
Severity
Graded, gateable scale
Each hit grades on a 5-step ordered scale (info → minor → moderate → severe → contraindicated). The response also returns severity_max so you can gate a dispense flow on one field.
Identifiers
Mixed identifier input
Reference drugs by ATC, internal ID, or { system, code } for Pharmacode / GTIN / NDC / PZN / CIP13 in the same request — all resolved to ATC server-side.
Honest gaps
Nothing fails silently
Inputs that do not resolve to an ATC come back in unresolved_drugs with the original echo, so a missing match is visible rather than dropped.
Try it
A real call, end to end
POST a list of drugs in any supported identifier system; get back the interacting pairs and an overall severity_max.
POST /api/v1/interactions/check
curl -X POST 'https://drug-database.com/api/v1/interactions/check' \
-H 'Authorization: Bearer dd_live_…' \
-H 'Content-Type: application/json' \
-d '{
"drugs": [
{ "atc_code": "B01AC06" },
{ "atc_code": "B01AA03" },
{ "system": "gtin", "code": "7680651870019" }
]
}'response
{
"interactions": [
{
"atc_a": "B01AA03",
"atc_b": "B01AC06",
"severity": "severe",
"mechanism": "Additive antiplatelet/anticoagulant effect",
"recommendation": "Avoid combination; monitor for bleeding.",
"last_reviewed": "2026-02-14"
}
],
"severity_max": "severe",
"unresolved_drugs": [],
"_meta": { "sources": ["epha", "bag_sl", "oddb"] }
}Coverage & sourcing
- 27,611 interaction pairs, keyed on WHO ATC so they apply across all 19 jurisdictions.
- Interaction content is data sourced from EPha, BAG-SL and oddb; each pair carries a last_reviewed date.
- Identifier resolution reuses the same alias index as the lookup endpoint — one molecule, many codes.
- Severity is an ordered enum, so severity_max is a safe single-field gate.
Good to know
- · Interaction checks need the interactions:write scope.
- · We surface public interaction data; it is not a substitute for clinical judgement.
FAQ
Common questions
Each interaction grades on a 5-step ordered scale: info, minor, moderate, severe, contraindicated. The response also returns severity_max so you can gate a dispense flow on a single field.
Yes. Send 2 to 50 drugs in one request. The API generates every unique pair from your list (N-way), checks each against the interactions table, and returns all hits — you do not pair them up yourself.
Each entry can be an ATC code ({ "atc_code": "B01AC06" }), an internal drug ID, or a market identifier ({ "system": "gtin", "code": "..." }). Identifiers and IDs are resolved to their ATC code server-side.
Anything that does not resolve to an ATC code is returned in unresolved_drugs with the original input echoed back, so nothing fails silently and you can surface it to the user.
It is aggregated from public sources — EPha, BAG-SL and oddb — and keyed on WHO ATC. Each pair carries a last_reviewed date. We are not affiliated with these sources, and the output is a data service, not clinical advice.
Ready when you are
Put interaction checks in production this afternoon.
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