HL7 RDS_O13 (Pharmacy/Treatment Dispense) | Integration Soup HL7 Reference Guide

HL7 RDS_O13 Pharmacy/Treatment Dispense

The pharmacy dispensed something against an existing medication order.

HL7 message structure RDS_O13 groups and segments from HL7 v2.5.1 Hide structure

These are the generated groups and segments for the version selected at the top of the page. The article explains the workflow, and this panel follows the chosen HL7 version.

Message Structure

Segment	Name	Required	Repeatable
MSH	Message Header	Yes	No
SFT	Software Segment	No	Yes
NTE	Notes and Comments	No	Yes
RDS_O13.PATIENT	Patient group	No	No
PID	Patient Identification	Yes	No
PD1	Patient Additional Demographic	No	No
NTE	Notes and Comments	No	Yes
AL1	Patient Allergy Information	No	Yes
RDS_O13.PATIENT_VISIT	Patient Visit group	No	No
PV1	Patient Visit	Yes	No
PV2	Patient Visit - Additional Information	No	No
RDS_O13.ORDER	Order group	Yes	Yes
ORC	Common Order	Yes	No
RDS_O13.TIMING	Timing group	No	Yes
TQ1	Timing/Quantity	Yes	No
TQ2	Timing/Quantity Relationship	No	Yes
RDS_O13.ORDER_DETAIL	Order Detail group	No	No
RXO	Pharmacy/Treatment Order	Yes	No
RDS_O13.ORDER_DETAIL_SUPPLEMENT	Order Detail Supplement group	No	No
NTE	Notes and Comments	Yes	Yes
RXR	Pharmacy/Treatment Route	Yes	Yes
RDS_O13.COMPONENT	Component group	No	Yes
RXC	Pharmacy/Treatment Component Order	Yes	No
NTE	Notes and Comments	No	Yes
RDS_O13.ENCODING	Encoding group	No	No
RXE	Pharmacy/Treatment Encoded Order	Yes	No
NTE	Notes and Comments	No	Yes
RDS_O13.TIMING_ENCODED	Timing Encoded group	Yes	Yes
TQ1	Timing/Quantity	Yes	No
TQ2	Timing/Quantity Relationship	No	Yes
RXR	Pharmacy/Treatment Route	Yes	Yes
RXC	Pharmacy/Treatment Component Order	No	Yes
RXD	Pharmacy/Treatment Dispense	Yes	No
NTE	Notes and Comments	No	Yes
RXR	Pharmacy/Treatment Route	Yes	Yes
RXC	Pharmacy/Treatment Component Order	No	Yes
RDS_O13.OBSERVATION	Observation group	No	Yes
OBX	Observation/Result	Yes	No
NTE	Notes and Comments	No	Yes
FT1	Financial Transaction	No	Yes

RDS_O13 reports a pharmacy or treatment dispense. It is normally created by the pharmacy/treatment application each time medication or treatment is dispensed to fill an existing order. Receivers use it to update medication availability, nursing workflows, dispense history, cabinets, inventory, and sometimes charge posting.

RDS is not the same as administration. It says the medication was dispensed or supplied. Whether the patient actually received it is a separate administration workflow, usually RAS_O17 or another MAR-driven message.

A small RDS example

MSH|^~\&|PHARM|CITYHOSP|MAR|CITYHOSP|20260715124500||RDS^O13^RDS_O13|RDS00001|P|2.5.1 PID|1||123456^^^CITYHOSP^MR||Smith^Jane^Anne^^Ms^^L||19800314|F PV1|1|I|WARD2^205^1^CITYHOSP ORC|RE|MED448811^EHR|RX998877^PHARM RXE|^^^20260715120000|AMOX500^Amoxicillin 500 mg capsule^L|1|CAP^capsule^UCUM|30|CAP^capsule^UCUM RXD|1|AMOX500^Amoxicillin 500 mg capsule^L|20260715124000|30|CAP^capsule^UCUM|RX998877^PHARM|30|CAP^capsule^UCUM|20260715124000|PHARM1^Main pharmacy^L RXR|PO^Oral^HL70162

What systems do with it

The pharmacy application sends RDS to nursing, clinical repositories, dispensing cabinet systems, integration engines, or billing systems. The receiver may compare the dispense to the encoded order, show that doses are available, decrement inventory, or prepare the MAR for administration.

RXD is the dispense segment. It carries the dispensed item, date/time, amount, package or quantity, dispense identifier, dispensing provider or location, and related details. Optional RXE and RXO groups can be included so the receiver can compare dispense data with the encoded or original order.

How to read the structure

The message has a patient group, then one or more order groups. Each order group starts with ORC, may carry requested or encoded order details, then requires RXD. Route and component information can appear after the dispense so the receiving system understands how the dispensed item relates to the treatment plan.

Financial transaction segments may also appear. That makes sense when a dispense is the event that drives a charge, but keep charging rules separate from clinical dispense history.

Implementation traps

Do not infer administration from dispense. A dose can be dispensed, returned, wasted, cancelled, or never given. If the receiver needs actual medication administration, look for RXA in RAS_O17 or an equivalent MAR event.

Also preserve dispense identifiers and quantities. Medication reconciliation and inventory logic often depend on distinguishing one 30-capsule dispense from thirty one-capsule administrations.

Reference notes

The HL7 v2+ RDS_O13 page describes RDS as a pharmacy/treatment application message created for each dispense to fill an existing order. Practical summaries such as iNTERFACEWARE's RDS guide describe the same dispense-centered workflow.