Myasthenia gravis and other myoneural disorders (G70) ICD-10-CM
The G70 code range covers myasthenia gravis and other myoneural disorders with 11 ICD-10-CM diagnosis codes. 8 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Codes in the G70 Range 11 codes · 8 billable
- G70 Myasthenia gravis and other myoneural disordersNon-billable
- G70.0 Myasthenia gravisNon-billable
- G70.00 Myasthenia gravis without (acute) exacerbation
- G70.01 Myasthenia gravis with (acute) exacerbation
- G70.1 Toxic myoneural disorders
- G70.2 Congenital and developmental myasthenia
- G70.8 Other specified myoneural disordersNon-billable
- G70.80 Lambert-Eaton syndrome, unspecified
- G70.81 Lambert-Eaton syndrome in disease classified elsewhere
- G70.89 Other specified myoneural disorders
- G70.9 Myoneural disorder, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the G70 range.
Lambert-Eaton Myasthenic Syndrome
An autoimmune disease characterized by weakness and fatigability of proximal muscles, particularly of the pelvic girdle, lower extremities, trunk, and shoulder girdle. There is relative sparing of extraocular and bulbar muscles. CARCINOMA, SMALL CELL of the lung is a frequently associated condition, although other malignancies and autoimmune diseases may be associated. Muscular weakness results from impaired impulse transmission at the NEUROMUSCULAR JUNCTION. Presynaptic calcium channel dysfunction leads to a reduced amount of acetylcholine being released in response to stimulation of the nerve. (From Adams et al., Principles of Neurology, 6th ed, pp 1471)
Myasthenia Gravis
A disorder of neuromuscular transmission characterized by fatigable weakness of cranial and skeletal muscles with elevated titers of ACETYLCHOLINE RECEPTORS or muscle-specific receptor tyrosine kinase (MuSK) autoantibodies. Clinical manifestations may include ocular muscle weakness (fluctuating, asymmetric, external ophthalmoplegia; diplopia; ptosis; and weakness of eye closure) and extraocular fatigable weakness of facial, bulbar, respiratory, and proximal limb muscles. The disease may remain limited to the ocular muscles (ocular myasthenia). THYMOMA is commonly associated with this condition.
About the G70 Code Range
These conditions involve the myoneural junction, where nerves meet muscles.
G70.0 separates myasthenia gravis by whether acute worsening is present. G70.1 identifies toxic myoneural disorders, while G70.2 identifies congenital and developmental myasthenia.
Within G70.8, Lambert-Eaton syndrome is separated by whether an associated disease is identified. Other specified myoneural disorders have a separate subdivision. G70.9 identifies an unspecified myoneural disorder.
Questions About This Page
How many billable codes are in the G70 range?
Of the 11 codes in this range, 8 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the G70 range classify?
The range classifies myasthenia gravis and other myoneural disorders. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
