IAR - Allergy Reaction Segment

The IAR segment is used to transmit a single reaction and information associated with this single reaction occurrence for a particular patient allergy (IAM – patient adverse reaction).

HL7 Attribute Table - IAR - Allergy Reaction Segment

Seq#	Data Element Name	DataType	Usage	Vocabulary	Cardinality	Item #	Length	C.LEN	Flags
IAR
1	Allergy Reaction Code	CWE	R		[1..1]	03296
2	Allergy Severity Code	CWE	R	0128 Allergy Severity	[1..1]	03297
3	Sensitivity to Causative Agent Code	CWE	O	0436 Sensitivity to Causative Agent Code	[0..1]	03298
4	Management	ST	O		[0..1]	03299		250	#

IAR-1: Allergy Reaction Code (CWE) 03296

Definition: This field identifies the specific allergic reaction that was documented. This element may conform to some external, standard coding system, or it may conform to local, largely textual or mnemonic descriptions (e.g., convulsions, sneeze, rash, etc.).

IAR-2: Allergy Severity Code (CWE) 03297

Definition: This field indicates the general severity of the allergy. Refer to User-defined Table 0128 - Allergy severity code in Chapter 2C, Code Tables, for suggested values.

IAR-3: Sensitivity to Causative Agent Code (CWE) 03298

Definition: This field contains the reason why the patient should not be exposed to a substance. Refer to User-defined Table 0436 - Sensitivity to causative Agent code in Chapter 2C, Code Tables, for suggested values.

IAR-4: Management (ST) 03299

Definition: This field contains a textual description of the actions that were performed in response to the reaction.