GET /elink.fcgi

nih.gov:pubmed-central-api

Summary: Link between databases
Operation ID: eLink
Auth: unknown
Description

Retrieves UIDs in one database linked to UIDs in another database.

Parameters (10)

WebEnv (string, query, optional)

Web environment string

cmd (string, query, optional, default: neighbor)

Command mode

Constraints: {'enum': ['neighbor', 'neighbor_score', 'neighbor_history', 'acheck', 'ncheck', 'lcheck', 'llinks', 'llinkslib', 'prlinks']}

db (string, query, optional)

Destination database (omit for all linked databases)

dbfrom (string, query, required)

Source database

email (string, query, optional)

Email address for contact

id (string, query, optional)

Comma-separated UIDs from source database

linkname (string, query, optional)

Specific link name (e.g., pmc_pubmed, pmc_pmc_cited)

query_key (string, query, optional)

Query key from previous search

retmode (string, query, optional, default: xml)

Return mode

Constraints: {'enum': ['xml', 'json']}

tool (string, query, optional)

Tool name for logging

Examples (3)

TitleTypeURLAction
Link PubMed IDs to PMC full text curl https://www.ncbi.nlm.nih.gov/pmc/elink.fcgi?dbfrom=pubmed&db=pmc&id=12345678&id=23456789&retmode=json&email=user@example.com&tool=robustapi
Find articles citing a PMC article curl https://www.ncbi.nlm.nih.gov/pmc/elink.fcgi?dbfrom=pmc&db=pmc&linkname=pmc_pmc_cited&id=PMC13901&retmode=json&email=user@example.com&tool=robustapi
Get all database links for a protein curl https://www.ncbi.nlm.nih.gov/pmc/elink.fcgi?dbfrom=protein&id=NP_001300&cmd=neighbor&retmode=json&email=user@example.com&tool=robustapi

Probe History

Latency

Status Codes

TimeStatusLatencySize
2026-03-23 10:35:15.314102 404 511ms
2026-03-23 10:25:55.750561 404 506ms
2026-03-23 09:23:40.683166 404 521ms

Response Changes

WhenOldNew
2026-03-23 10:25:55.750561 161bdf726c36 3db5d6789dbc
2026-03-23 10:35:15.314102 3db5d6789dbc eeb91af69db7