ICD-11 classes
X Extension Codes
Substances
Allergens
ICD-11 Allergens
An allergen is any substance (antigen), eaten, inhaled or exposed to the skin, that is recognised by the immune system and causes an allergic reaction, such as rhinitis, asthma, food and drug hypersensitivity, skin reactions and anaphylaxis.
The diagnosis includes nothing.
The diagnosis excludes nothing.
Diagnosis contains 3 clarifying diagnoses:
- Low molecular weight haptens
It contains 14 clarifying diagnoses. - Low molecular weight photohaptens
It contains 5 clarifying diagnoses. - High molecular weight allergens
It contains 1 clarifying diagnosis.
The diagnosis is coded elsewhere:
- Aetiology #30484
- Substances #42918
- Extension codes of particular relevance to skin diseases #63451