RXA — Pharmacy/Treatment Administration
Appears in RAS (pharmacy administration) messages. One RXA per administration event.
The RXA segment records the details of a medication or treatment administration event. It documents what was given, how much, when, by whom, and what lot number was used. It appears in RAS messages for medication administration records.
Real-World Context
RXA is the eMAR record in HL7. It documents every medication administration event. The combination of administered code (RXA.5), amount (RXA.6), and datetime (RXA.3) must match what the nurse documented at the bedside. Lot numbers in RXA.15 are critical for vaccine adverse event reporting — missing lot numbers prevent timely VAERS reporting.
Field Reference
Click any row to see the full description, common values, and troubleshooting tip.
| # | Field Name | Type | Req | Max Len | |
|---|---|---|---|---|---|
| 1 | Give Sub-ID Counter | NM | R | 4 | ▶ |
| 2 | Administration Sub-ID Counter | NM | R | 4 | ▶ |
| 3 | Date/Time Start of Administration | TS | R | 26 | ▶ |
| 4 | Date/Time End of Administration | TS | R | 26 | ▶ |
| 5 | Administered Code | CE | R | 250 | ▶ |
| 6 | Administered Amount | NM | R | 20 | ▶ |
| 7 | Administered Units | CE | O | 250 | ▶ |
| 8 | Administered Dosage Form | CE | O | 250 | ▶ |
| 9 | Administration Notes | CE | O | 250 | ▶ |
| 10 | Administering Provider | XCN | O | 250 | ▶ |
| 11 | Administered-at Location | LA2 | O | 200 | ▶ |
| 12 | Administered Per (Time Unit) | ST | O | 20 | ▶ |
| 13 | Administered Strength | NM | O | 20 | ▶ |
| 14 | Administered Strength Units | CE | O | 250 | ▶ |
| 15 | Substance Lot Number | ST | O | 20 | ▶ |
| 16 | Substance Expiration Date | TS | O | 26 | ▶ |
| 17 | Substance Manufacturer Name | CE | O | 250 | ▶ |
| 18 | Substance/Treatment Refusal Reason | CE | O | 250 | ▶ |
| 19 | Indication | CE | O | 250 | ▶ |
| 20 | Completion Status | ID | O | 2 | ▶ |
| 21 | Action Code - RXA | ST | O | 2 | ▶ |
| 22 | System Entry Date/Time | TS | O | 26 | ▶ |
| 23 | Administered Drug Strength Volume | NM | O | 5 | ▶ |
| 24 | Administered Drug Strength Volume Units | CWE | O | 705 | ▶ |
| 25 | Administered Barcode Identifier | CWE | O | 705 | ▶ |
Example Segment
1RXA||0|1|20260310143205|20260310143205|0069-0530-83^Amoxicillin 500mg^NDC|500|mg^milligrams^UCUM|CAP^Capsule|ORAL^Oral|6789012345^WILLIAMS^SARAH^^^RN^NPI|||500|mg^milligrams^UCUM|LOT20260101A|20270101|MSD^Merck^NDC|||J18.9^Pneumonia^ICD10|CP
Related Segments
Used In Message Types
Parse messages with RXA in real time
Paste any HL7 message into our free viewer. Decodes every segment and field instantly, client-side.
Open HL7 Message Viewer →Need HL7 mapping templates?
The HL7 Integration Toolkit includes field mapping worksheets, interface spec templates, and a go-live checklist for every major HL7 message type.
View HL7 Integration Toolkit →