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AL1 - Patient Allergy Information Segment

The AL1 segment contains patient allergy information of various types. Most of this information will be derived from user-defined tables. Each AL1 segment describes a single patient allergy.

HL7 Attribute Table - AL1 - Patient Allergy Information Segment
Seq# DataElement Description Must Implement Flags Cardinality Length C.LEN Vocabulary DataType
AL1
1 00203 Set ID - AL1 SHALL [1..1] [1..4] SI
2 00204 Allergen Type Code [0..1] CWE
3 00205 Allergen Code/Mnemonic/Description [0..1] CWE
4 00206 Allergy Severity Code [0..1] CWE
5 00207 Allergy Reaction Code = [0..*] 15 ST
6 00208 Identification Date SHALL NOT W [0..0]

AL1-1: Set ID - AL1 (SI) 00203

Definition: This field contains the number that identifies this transaction. For the first occurrence of the segment, the sequence number shall be one, for the second occurrence, the sequence number shall be two, etc.

AL1-2: Allergen Type Code (CWE) 00204

(Definition from AL1.2 in Ch. 3)

Definition: This field indicates a general allergy category (drug, food, pollen, etc.). Refer to User-defined Table 0127 - Allergen Type in Chapter 2C, Code Tables, for suggested values.

(Definition from IAM.2 in Ch. 3)

Definition: This field indicates a general allergy category (drug, food, pollen, etc.). Refer to User-defined Table 0127 - Allergen Type in Chapter 2C, Code Tables, for suggested values.

AL1-3: Allergen Code/Mnemonic/Description (CWE) 00205

(Definition from AL1.3 in Ch. 3)

Definition: This field uniquely identifies a particular allergen. This element may conform to some external, standard coding system (that must be identified), or it may conform to local, largely textual or mnemonic descriptions.

(Definition from IAM.3 in Ch. 3)

Definition: This field uniquely identifies a particular allergen. This element may conform to some external, standard coding system (that must be identified), or it may conform to local, largely textual or mnemonic descriptions.

If a system maintains allergen codes as its unique identifier for a particular allergy, and two systems have agreed to process the IAM using update mode, then this field can be used as the unique identifier instead of IAM-8 - Allergy Unique Identifier. This does not preclude using allergen codes for unique identifiers for snapshot processing.

AL1-4: Allergy Severity Code (CWE) 00206

(Definition from AL1.4 in Ch. 3)

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

(Definition from IAM.4 in Ch. 3)

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.

AL1-5: Allergy Reaction Code (ST) 00207

(Definition from AL1.5 in Ch. 3)

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.).

(Definition from IAM.5 in Ch. 3)

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.).

AL1-6: Identification Date

Definition: The Al-6 field was retained for backward compatibility only as of v 2.4 and has been withdrawn as of v 2.7. The reader is referred to the IAM-11 – Onset Date or IAM-13 – Inset Date fields for dates when the allergy was identified..