68 · KEGG Drug

Approved drugs — structures, targets, pathways & drug-drug interactions Category: Drug-centric | Type: DB | Subcategory: DDI API: https://rest.kegg.jp (free, no key required for academic use)

Resource	URL
Homepage	https://www.genome.jp/kegg/
API docs	https://www.kegg.jp/kegg/docs/keggapi.html
Paper	https://academic.oup.com/nar/article/38/suppl_1/D355/3112250

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What it provides

• Drug metadata: name, formula, molecular weight, efficacy, class
• Targets: gene/protein targets for each approved drug
• Interactions (DDI): drug-drug interaction annotations
• Pathways: linked KEGG pathway IDs

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Quick start

from 68_KEGG_Drug import query

# Single entity
results = query("aspirin")

# Multiple entities
results = query(["aspirin", "metformin", "imatinib"])

# By KEGG Drug ID
results = query("D00109")

# Specific fields only
results = query("warfarin", fields="targets")
results = query("warfarin", fields="interactions")

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query() interface

query(entities, fields="all") -> list[dict]

Parameter	Type	Description
entities	str | list[str]	Drug name(s) or KEGG Drug ID(s) (e.g. "D00109")
fields	str	"all" — full entry; "targets" — targets only; "interactions" — DDI only

Return structure (fields="all")

[
  {
    "drug_id": "dr:D00109",
    "query": "aspirin",
    "name": "Aspirin (JP18/USP/INN); ...",
    "formula": "C9H8O4",
    "mol_weight": "180.0423",
    "targets": ["PTGS1 ...", "PTGS2 ..."],
    "interactions": ["Warfarin [precaution] ...", ...],
    "pathways": ["map07112 ...", ...],
    "classes": ["Analgesic ...", ...]
  }
]

If a name cannot be resolved, the entry contains {"query": "xxx", "error": "No match found"}.

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Lower-level functions

Function	Input	Output	Description
search(query, limit=10)	drug name/keyword	list[{id, name}]	Keyword search
get_entry(drug_id)	KEGG Drug ID	dict	Full parsed entry
get_targets(drug_id)	KEGG Drug ID	list[str]	Target lines
get_interactions(drug_id)	KEGG Drug ID	list[str]	DDI lines

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Notes

• KEGG REST API is free for academic use; commercial use requires a license.
• Rate limit: no official cap, but keep requests reasonable (~1 req/sec).
• Drug IDs look like D00109 or dr:D00109; both formats accepted.
• Not all drugs have interaction or target annotations — empty list means no data.