2026 ICD-10-CM Diagnosis Code G70.01Myasthenia gravis with (acute) exacerbation

ICD-10-CM Codes›G00–G99›G70-G73›G70

ICD-10-CM G70.01
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G70.01 is a billable ICD-10-CM diagnosis code for myasthenia gravis with (acute) exacerbation. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as myasthenia gravis with exacerbation. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Myopathies.

Code Identity

ICD-10-CM Code
G70.01
Billable Status
Yes — Valid for Submission
Code Describes
Myasthenia gravis with (acute) exacerbation
Short Description
Myasthenia gravis with (acute) exacerbation
Same as the full description in the CMS dataset.
Parent Code
G70.0
Myasthenia gravis

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG70-G73Diseases of myoneural junction and muscle
CategoryG70Myasthenia gravis and other myoneural disorders
This CodeG70.01Myasthenia gravis with (acute) exacerbation

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Myasthenia gravis with exacerbation
  • Myasthenic crisis

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Myasthenia gravis in crisis

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Erb-Goldflam disease or syndrome
      • with exacerbation (acute)
    • Erb-Goldflam disease or syndrome
      • in crisis
    • Goldflam-Erb disease or syndrome
      • with exacerbation (acute)
    • Goldflam-Erb disease or syndrome
      • in crisis
    • Myasthenia
      • gravis
        • with exacerbation (acute)
    • Myasthenia
      • gravis
        • in crisis
    • Myasthenia
      • gravis
        • pseudoparalytica
          • with exacerbation (acute)
    • Myasthenia
      • gravis
        • pseudoparalytica
          • in crisis
    • Paralysis, paralytic(complete) (incomplete)
      • asthenic bulbar
        • with exacerbation (acute)
    • Paralysis, paralytic(complete) (incomplete)
      • asthenic bulbar
        • in crisis
    • Paralysis, paralytic(complete) (incomplete)
      • bulbospinal
        • with exacerbation (acute)
    • Paralysis, paralytic(complete) (incomplete)
      • bulbospinal
        • in crisis
    • Syndrome
      • Hoppe-Goldflam
        • with exacerbation (acute)
    • Syndrome
      • Hoppe-Goldflam
        • in crisis
    • Syndrome
      • pseudoparalytica
        • with exacerbation (acute)
    • Syndrome
      • pseudoparalytica
        • in crisis

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NVS018
Myopathies
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • 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.

  • Myasthenia Gravis, Autoimmune, Experimental

    any autoimmune animal disease model used in the study of myasthenia gravis. injection with purified neuromuscular junction acetylcholine receptor (achr) (see receptors, cholinergic) components results in a myasthenic syndrome that has acute and chronic phases. the motor endplate pathology, loss of acetylcholine receptors, presence of circulating anti-achr antibodies, and electrophysiologic changes make this condition virtually identical to human myasthenia gravis. passive transfer of achr antibodies or lymphocytes from afflicted animals to normals induces passive transfer experimental autoimmune myasthenia gravis. (from joynt, clinical neurology, 1997, ch 54, p3)

  • Myasthenia Gravis, Neonatal

    a disorder of neuromuscular transmission that occurs in a minority of newborns born to women with myasthenia gravis. clinical features are usually present at birth or develop in the first 3 days of life and consist of hypotonia and impaired respiratory, suck, and swallowing abilities. this condition is associated with the passive transfer of acetylcholine receptor antibodies through the placenta. in the majority of infants the myasthenic weakness resolves (i.e., transient neonatal myasthenia gravis) although this disorder may rarely continue beyond the neonatal period (i.e., persistent neonatal myasthenia gravis). (from menkes, textbook of child neurology, 5th ed, p823; neurology 1997 jan;48(1):50-4)

  • Myasthenic Syndromes, Congenital

    a heterogeneous group of disorders characterized by a congenital defect in neuromuscular transmission at the neuromuscular junction. this includes presynaptic, synaptic, and postsynaptic disorders (that are not of autoimmune origin). the majority of these diseases are caused by mutations of various subunits of the nicotinic acetylcholine receptor (receptors, nicotinic) on the postsynaptic surface of the junction. (from arch neurol 1999 feb;56(2):163-7)

Patient EducationClinical

Myasthenia Gravis

Myasthenia gravis, sometimes called MG, is a chronic (long-lasting) disease that causes weakness in your voluntary muscles. The voluntary muscles are the ones that you can control. They include the muscles you use for:

The full article covers:

  • What is myasthenia gravis?
  • What causes myasthenia gravis?
  • Who is more likely to develop myasthenia gravis?
  • What are the symptoms of myasthenia gravis?
  • How is myasthenia gravis diagnosed?
  • What are the treatments for myasthenia gravis?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert G70.01 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
358.01 Myasthna gravs w ac exac
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About G70.01Overview

Is G70.01 (Myasthenia gravis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report myasthenia gravis with (acute) exacerbation on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What is the ICD-9 equivalent of G70.01?

Under the General Equivalence Mappings, myasthenia gravis with (acute) exacerbation converts to ICD-9-CM 358.01 (myasthna gravs w ac exac). The mapping is a direct match.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.