ICD-10 Code for Diphtheria
Also indexed as (gangrenous) (hemorrhagic)
The ICD-10-CM code for diphtheria is A36.9 — Diphtheria, unspecified. This is the code the Alphabetic Index gives for diphtheria with no further qualifier, valid for FY2027 (October 1, 2026 – September 30, 2027).
A36.9 is billable but unspecified. If the documentation names a type, site or cause, one of the more specific codes below is likely expected.
Which diphtheria code should you use?
The Alphabetic Index lists 8 codes under Diphtheria, diphtheritic. 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
| carrier | Z22.2 | Carrier of diphtheria |
| cutaneous | A36.3 | Cutaneous diphtheria |
| faucial | A36.0 | Pharyngeal diphtheria |
| infection of wound | A36.3 | Cutaneous diphtheria |
| laryngeal | A36.2 | Laryngeal diphtheria |
| myocarditis | A36.81 | Diphtheritic cardiomyopathy |
| nasal, anterior | A36.89 | Other diphtheritic complications |
| nasopharyngeal | A36.1 | Nasopharyngeal diphtheria |
| neurological complication | A36.89 | Other diphtheritic complications |
| pharyngeal | A36.0 | Pharyngeal diphtheria |
| specified site NEC | A36.89 | Other diphtheritic complications |
| tonsillar | A36.0 | Pharyngeal diphtheria |
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