G71.12
Myotonia congenita
Billable FY2026 2025-10-01 → 2026-09-30
Exclusions 11 never code together
G71code
G00-G99chapter
Excludes2
- certain conditions originating in the perinatal period (P04-P96)P04-P96
- certain infectious and parasitic diseases (A00-B99)A00-B99
- complications of pregnancy, childbirth and the puerperium (O00-O9A)O00-O9A
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)Q00-Q99
- endocrine, nutritional and metabolic diseases (E00-E88)E00-E88
- injury, poisoning and certain other consequences of external causes (S00-T88)S00-T88
- neoplasms (C00-D49)C00-D49
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)R00-R94
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 4
G71.12code
Inclusion terms
- Acetazolamide responsive myotonia congenita
- Dominant myotonia congenita [Thomsen disease]
- Myotonia levior
- Recessive myotonia congenita [Becker disease]
Index entries leading here 4
Alongside this code 4 same parent — G71.1
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.