Episodic and paroxysmal disorders (G40-G47) ICD-10-CM
The G40–G47 section covers episodic and paroxysmal disorders with 307 ICD-10-CM diagnosis codes, of which 205 are billable in fiscal year 2027. The section is organized into the 6 code ranges listed below.
Code Ranges in This Section 6 ranges · 307 codes
The info icon previews the code ranges inside each row and its instructional notations from the official Tabular List.
About the G40–G47 Code Range
Seizures, headaches, temporary brain circulation attacks, brain blood vessel syndromes, and sleep problems make up this group of nervous system conditions.
G40 separates epilepsy and recurrent seizures by focal or generalized patterns, external causes, and named syndromes. G43 separates migraines by features such as aura, chronic symptoms, and persistent aura. Migraine involves recurring, one-sided, throbbing headaches; an aura involves neurological symptoms. G44 groups other headaches by type or cause, including cluster, tension-type, post-traumatic, and drug-induced headaches.
G45 includes temporary attacks involving reduced blood flow to the brain and related syndromes, with subdivisions for named arteries and other symptoms. G46 separates brain blood vessel syndromes by named artery, brain region, or motor and sensory features. G47 separates sleep disorders by changes in sleep, sleep rhythm, breathing, or movement.
Questions About This Page
How many codes are in the G40-G47 range?
The G40-G47 range contains 307 ICD-10-CM diagnosis codes in FY 2027. 205 of them are billable, and the rest are category headers that organize the section.
What conditions does G40-G47 cover?
The range covers episodic and paroxysmal disorders. The code ranges listed above break it into groups of related conditions, and each one links to its own page with the full code list.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
