RXO — Pharmacy/Treatment Order
Appears in OMP (pharmacy order) and OMS (stock requisition) messages. Precedes RXE in the order workflow.
The RXO segment carries the original pharmacy or treatment order as entered by the prescriber. It is the initial request before pharmacist review and encoding into RXE.
Real-World Context
RXO represents what the physician ordered before pharmacy processes it. The requested give code in RXO.1 is the drug as the prescriber thought of it — often a brand name or generic name without specific NDC. The pharmacy then converts this to a specific NDC in RXE.2. If the physician's order is not visible in the pharmacy system, the RXO segment is not being transmitted or processed.
Field Reference
Click any row to see the full description, common values, and troubleshooting tip.
| # | Field Name | Type | Req | Max Len | |
|---|---|---|---|---|---|
| 1 | Requested Give Code | CE | R | 250 | ▶ |
| 2 | Requested Give Amount - Minimum | NM | R | 20 | ▶ |
| 3 | Requested Give Amount - Maximum | NM | O | 20 | ▶ |
| 4 | Requested Give Units | CE | R | 250 | ▶ |
| 5 | Requested Dosage Form | CE | O | 250 | ▶ |
| 6 | Provider's Pharmacy/Treatment Instructions | CE | O | 250 | ▶ |
| 7 | Provider's Administration Instructions | CE | O | 250 | ▶ |
| 8 | Deliver-to Location | LA1 | O | 200 | ▶ |
| 9 | Allow Substitutions | ID | O | 1 | ▶ |
| 10 | Requested Dispense Code | CE | O | 250 | ▶ |
| 11 | Requested Dispense Amount | NM | O | 20 | ▶ |
| 12 | Requested Dispense Units | CE | O | 250 | ▶ |
| 13 | Number of Refills | NM | O | 3 | ▶ |
| 14 | Ordering Provider's DEA Number | XCN | O | 250 | ▶ |
| 15 | Pharmacist/Treatment Supplier's Verifier ID | XCN | O | 250 | ▶ |
| 16 | Needs Human Review | ID | O | 1 | ▶ |
| 17 | Requested Give Per (Time Unit) | ST | O | 20 | ▶ |
| 18 | Requested Give Strength | NM | O | 20 | ▶ |
| 19 | Requested Give Strength Units | CE | O | 250 | ▶ |
| 20 | Indication | CE | O | 250 | ▶ |
| 21 | Requested Give Rate Amount | ST | O | 6 | ▶ |
| 22 | Requested Give Rate Units | CE | O | 250 | ▶ |
| 23 | Total Daily Dose | CQ | O | 10 | ▶ |
| 24 | Supplementary Code | CE | O | 250 | ▶ |
Example Segment
1RXO||AMOX500^Amoxicillin 500mg^LOCAL|500|1000|mg^milligrams^UCUM|CAP^Capsule|NO_SUBSTITUTION^Do not substitute|IV_SLOW^Give with food|4NORTH^401^A^MAIN|N|||0|||Y|||500|mg^milligrams^UCUM|J18.9^Pneumonia^ICD10
Related Segments
Used In Message Types
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