| entrez_citmatch | Fetch pubmed ids matching specially formatted citation strings | 
| entrez_dbs | List databases available from the NCBI | 
| entrez_db_links | List available links for records from a given NCBI database | 
| entrez_db_searchable | List available search fields for a given database | 
| entrez_db_summary | Retrieve summary information about an NCBI database | 
| entrez_fetch | Download data from NCBI databases | 
| entrez_global_query | Find the number of records that match a given term across all NCBI Entrez databases | 
| entrez_info | Get information about EUtils databases | 
| entrez_link | Get links to datasets related to records from an NCBI database | 
| entrez_post | Post IDs to Eutils for later use | 
| entrez_search | Search the NCBI databases using EUtils | 
| entrez_summary | Get summaries of objects in NCBI datasets from a unique ID | 
| extract_from_esummary | Extract elements from a list of esummary records | 
| linkout_urls | Extract URLs from an elink object | 
| parse_pubmed_xml | Summarize an XML record from pubmed. | 
| set_entrez_key | Set the ENTREZ_KEY variable to be used by all rentrez functions |