ICD-10 Code for Allergy
Also indexed as (reaction) (to)
The ICD-10-CM code for allergy is T78.40 — Allergy, unspecified. This is the code the Alphabetic Index gives for allergy with no further qualifier, valid for FY2027 (October 1, 2026 – September 30, 2027).
Not billable
T78.40 cannot be submitted on a claim. It is a header code, so a more specific code from the list below is required.
Which allergy code should you use?
The Alphabetic Index lists 57 codes under Allergy, allergic. Which one applies depends on the qualifier documented in the record — the type, site, cause, or associated condition. Find the qualifier below, then verify the code in the Tabular List before using it.
By type
| air-borne substance NEC | J30.89 | Other allergic rhinitis | |
| alveolitis | J67.9 | Hypersensitivity pneumonitis due to unspecified organic dust | |
| anaphylactic reaction or shock | T78.2 | Anaphylactic shock, unspecified | not billable |
| angioneurotic edema | T78.3 | Angioneurotic edema | not billable |
| animal | J30.81 | Allergic rhinitis due to animal (cat) (dog) hair and dander | |
| bee sting | T63.44 | Toxic effect of venom of bees | not billable |
| colitis | K52.29 | Other allergic and dietetic gastroenteritis and colitis | |
| dairy products | T78.119 | Other adverse food reaction due to milk and dairy products with baked milk tolerance/reactivity, unspecified | not billable |
| dander | J30.81 | Allergic rhinitis due to animal (cat) (dog) hair and dander | |
| dandruff | J30.81 | Allergic rhinitis due to animal (cat) (dog) hair and dander | |
| dental restorative material | K08.55 | Allergy to existing dental restorative material | |
| drug, medicament & biological | T78.40 | Allergy, unspecified | not billable |
| due to pollen | J30.1 | Allergic rhinitis due to pollen | |
| dust | J30.89 | Other allergic rhinitis | |
| epidermal | J30.81 | Allergic rhinitis due to animal (cat) (dog) hair and dander | |
| feathers | J30.89 | Other allergic rhinitis | |
| foodNEC | T78.19 | Other adverse food reactions, not elsewhere classified | not billable |
| grain | J30.1 | Allergic rhinitis due to pollen | |
| grass | J30.1 | Allergic rhinitis due to pollen | |
| hair | J30.81 | Allergic rhinitis due to animal (cat) (dog) hair and dander | |
| inhalant | J30.89 | Other allergic rhinitis | |
| kapok | J30.89 | Other allergic rhinitis | |
| milk protein | Z91.0110 | Allergy to milk products, unspecified | |
| nasal, seasonal due to pollen | J30.1 | Allergic rhinitis due to pollen | |
| pneumonia | J82.89 | Other pulmonary eosinophilia, not elsewhere classified | |
| pollen | J30.1 | Allergic rhinitis due to pollen | |
| primrose | J30.1 | Allergic rhinitis due to pollen | |
| primula | J30.1 | Allergic rhinitis due to pollen | |
| proctocolitis | K52.29 | Other allergic and dietetic gastroenteritis and colitis | |
| purpura | D69.0 | Allergic purpura | |
| ragweed | J30.1 | Allergic rhinitis due to pollen | |
| rose | J30.1 | Allergic rhinitis due to pollen | |
| seasonal NEC | J30.2 | Other seasonal allergic rhinitis | |
| Senecio jacobae | J30.1 | Allergic rhinitis due to pollen | |
| serum | T80.69 | Other serum reaction due to other serum | not billable |
| shock | T78.2 | Anaphylactic shock, unspecified | not billable |
| specific NEC | T78.49 | Other allergy | not billable |
| tree | J30.1 | Allergic rhinitis due to pollen | |
| upper respiratory | J30.9 | Allergic rhinitis, unspecified | |
| urticaria | L50.0 | Allergic urticaria |
Allergy alveolitis
Allergy dairy products
| anaphylactic reaction | T78.079 | Anaphylactic reaction due to milk and dairy products, unspecified | not billable |
| with › reactivity to baked milk | T78.111 | Other adverse food reaction due to milk and dairy products with reactivity to baked milk | not billable |
| with › tolerance to baked milk | T78.110 | Other adverse food reactions due to milk and dairy products with tolerance to baked milk | not billable |
| anaphylactic reaction › with › reactivity to baked milk | T78.071 | Anaphylactic reaction due to milk and dairy products with reactivity to baked milk | not billable |
| anaphylactic reaction › with › tolerance to baked milk | T78.070 | Anaphylactic reaction due to milk and dairy products with tolerance to baked milk | not billable |
Allergy eggs
| adverse reaction NEC | T78.129 | Other adverse food reaction due to egg with baked egg tolerance/reactivity, unspecified | not billable |
| anaphylactic reaction | T78.089 | Anaphylactic reaction due to eggs, unspecified | not billable |
| adverse reaction NEC › with › reactivity to baked egg | T78.121 | Other adverse food reaction due to egg with reactivity to baked egg | not billable |
| adverse reaction NEC › with › tolerance to baked egg | T78.120 | Other adverse food reaction due to egg with tolerance to baked egg | not billable |
| anaphylactic reaction › with › reactivity to baked egg | T78.081 | Anaphylactic reaction due to egg with reactivity to baked egg | not billable |
| anaphylactic reaction › with › tolerance to baked egg | T78.080 | Anaphylactic reaction due to egg with tolerance to baked egg | not billable |
Allergy foodNEC
| dietary counseling and surveillance | Z71.3 | Dietary counseling and surveillance | |
| in contact with skin | L23.6 | Allergic contact dermatitis due to food in contact with the skin | |
| rhinitis | J30.5 | Allergic rhinitis due to food | |
| status | Z91.018 | Allergy to other foods | |
| status › beef | Z91.014 | Allergy to mammalian meats | |
| status › eggs | Z91.0120 | Allergy to eggs, unspecified | |
| status › lamb | Z91.014 | Allergy to mammalian meats | |
| status › mammalian meats | Z91.014 | Allergy to mammalian meats | |
| status › milk products | Z91.0110 | Allergy to milk products, unspecified | |
| status › peanuts | Z91.010 | Allergy to peanuts | |
| status › pork | Z91.014 | Allergy to mammalian meats | |
| status › red meats | Z91.014 | Allergy to mammalian meats | |
| status › seafood | Z91.013 | Allergy to seafood | |
| status › specified NEC | Z91.018 | Allergy to other foods | |
| status › eggs › with › reactivity to baked egg | Z91.0122 | Allergy to eggs with reactivity to baked egg | |
| status › eggs › with › tolerance to baked egg | Z91.0121 | Allergy to eggs with tolerance to baked egg | |
| status › milk products › with › reactivity to baked milk | Z91.0112 | Allergy to milk products with reactivity to baked milk | |
| status › milk products › with › tolerance to baked milk | Z91.0111 | Allergy to milk products with tolerance to baked milk |
Allergy gastrointestinal
Allergy inhalant
| pollen | J30.1 | Allergic rhinitis due to pollen |
Allergy milk protein
| adverse reaction NEC | T78.119 | Other adverse food reaction due to milk and dairy products with baked milk tolerance/reactivity, unspecified | not billable |
| anaphylactic reaction | T78.079 | Anaphylactic reaction due to milk and dairy products, unspecified | not billable |
| dermatitis | L27.2 | Dermatitis due to ingested food | |
| enterocolitis syndrome | K52.21 | Food protein-induced enterocolitis syndrome | |
| enteropathy | K52.22 | Food protein-induced enteropathy | |
| gastroenteritis | K52.29 | Other allergic and dietetic gastroenteritis and colitis | |
| gastroesophageal reflux | K21.9 | Gastro-esophageal reflux disease without esophagitis | |
| proctocolitis | K52.29 | Other allergic and dietetic gastroenteritis and colitis | |
| with › reactivity to baked milk | Z91.0112 | Allergy to milk products with reactivity to baked milk | |
| with › tolerance to baked milk | Z91.0111 | Allergy to milk products with tolerance to baked milk | |
| gastroesophageal reflux › with esophagitis | K21.00 | Gastro-esophageal reflux disease with esophagitis, without bleeding | |
| adverse reaction NEC › with › reactivity to baked milk | T78.111 | Other adverse food reaction due to milk and dairy products with reactivity to baked milk | not billable |
| adverse reaction NEC › with › tolerance to baked milk | T78.110 | Other adverse food reactions due to milk and dairy products with tolerance to baked milk | not billable |
| anaphylactic reaction › with › reactivity to baked milk | T78.071 | Anaphylactic reaction due to milk and dairy products with reactivity to baked milk | not billable |
| anaphylactic reaction › with › tolerance to baked milk | T78.070 | Anaphylactic reaction due to milk and dairy products with tolerance to baked milk | not billable |
| gastroesophageal reflux › with esophagitis › with bleeding | K21.01 | Gastro-esophageal reflux disease with esophagitis, with bleeding |
Allergy serum
| anaphylactic shock | T80.59 | Anaphylactic reaction due to other serum | not billable |
Allergy shock
| due to › administration of blood and blood products | T80.51 | Anaphylactic reaction due to administration of blood and blood products | not billable |
| due to › adverse effect of correct medicinal substance properly administered | T88.6 | Anaphylactic reaction due to adverse effect of correct drug or medicament properly administered | not billable |
| due to › immunization | T80.52 | Anaphylactic reaction due to vaccination | not billable |
| due to › serum NEC | T80.59 | Anaphylactic reaction due to other serum | not billable |
| due to › vaccination | T80.52 | Anaphylactic reaction due to vaccination | not billable |
Codes under T78.40
Index terms and codes are reproduced from the official ICD-10-CM FY2027 release. The Alphabetic Index is a finding aid — a code must always be verified in the Tabular List before it is reported. Data sources