ICD-10 Code for Myasthenia

The default ICD-10-CM 2027 code for myasthenia is G70.9 – Myoneural disorder, unspecified. More specific codes depend on the details documented, as listed in the official index (11 codes, 11 billable).

Main code: G70.9 – Myoneural disorder, unspecified
Billable: Yes

Index entries for Myasthenia

congenital – G70.2
cordis – see Failure, heart
developmental – G70.2
gravis – G70.00
- with exacerbation (acute) – G70.01
- in crisis – G70.01
- neonatal, transient – P94.0
- pseudoparalytica – G70.00
  - with exacerbation (acute) – G70.01
  - in crisis – G70.01
stomach, psychogenic – F45.8
syndrome
- in
  - diabetes mellitus – see E08-E13 with .44
  - neoplastic disease – D49.9 – G73.3 [manifestation] – see also Neoplasm
  - pernicious anemia – D51.0 – G73.3 [manifestation]
  - thyrotoxicosis – E05.90 – G73.3 [manifestation]
    - with thyroid storm – E05.91 – G73.3 [manifestation]

How to choose the right code

Start with the main term, then pick the indented subterm that matches the documentation (type, cause, site, laterality, episode of care). Always confirm the code in the tabular list: follow its Excludes1/Excludes2, “code first” and “use additional code” notes, and add a 7th character where required.

Source: CDC/NCHS ICD-10-CM FY2027 alphabetic index.