ICD-10 Code for Nervous System Diseases: G00-G99 Comprehensive Guide

8 min

ICD 10 Code G00-G99 pertains to "Diseases of the Nervous System." These codes classify a wide range of neurological and nervous system disorders.

The nervous system functions as the intricate communication network of the human body. It can be likened to the body's electrical wiring, transmitting signals that control movements, sensations, and cognitive functions.

This complex system comprises two principal components:

Central Nervous System (CNS): Comprising the brain and spinal cord, the CNS serves as the command center of the body.
Peripheral Nervous System (PNS): The PNS extends from the CNS, forming a network of nerves that facilitates communication between the brain and the rest of the body.

ICD-10-CM Code G00-G09: Inflammatory Diseases of the Central Nervous System

ICD-10-CM Code G00-G09 covers conditions involving inflammation within the brain, spinal cord, and associated structures. The scope of these codes encompasses various diseases, disorders, and infections affecting the central nervous system, including acute and chronic conditions.

Key ICD-10-CM Codes for Inflammatory Diseases of the Central Nervous System
ICD Code	Description	Diagnosis
G00.0	Bacterial Meningitis	Bacterial infection causes inflammation of the meninges.
G03.9	Meningitis Due to Unspecified Cause	Meningitis without a specified cause, which could be viral, fungal, or of unknown origin.
G04.0	Acute Disseminated Encephalomyelitis	Acute inflammation of the brain and spinal cord, typically triggered by an infection or vaccination.
G06.0	Intracranial Abscess and Granuloma	An abscess or granuloma within the brain, often due to infections.
G08	Intracranial and Intraspinal Phlebitis and Thrombophlebitis	Inflammation in the veins of the central nervous system, potentially leading to clot formation.
G02.0	Meningococcal Meningitis	Meningitis caused by Neisseria meningitidis bacteria.
G04.1	Postinfectious Encephalitis	Encephalitis following an infection, such as a viral illness.
G06.1	Intracranial Abscess	Abscess within the brain, often resulting from infection.
G08.0	Intracranial Phlebitis	Inflammation within the veins of the brain.
G09	Sequelae of Inflammatory Diseases of the Central Nervous System	Long-term effects or complications of inflammatory CNS diseases, such as neurological deficits following a previous episode of meningitis or encephalitis.

Further Reading:

ICD-10-CM Code G10-G14: Systemic Atrophies Affecting the Central Nervous System

These codes encompass a group of neurodegenerative disorders characterized by the progressive and widespread degeneration of nerve cells in the central nervous system. The scope of these codes includes conditions that primarily affect the brain, spinal cord, and sometimes peripheral nerves.

Key ICD-10-CM Codes for Systemic Atrophies Affecting the Central Nervous System
ICD Code	Description	Diagnosis
G10.0	Huntington's Disease	Diagnosis of Huntington's disease, a hereditary neurodegenerative disorder characterized by motor dysfunction and cognitive decline.
G11.1	Autosomal Recessive Cerebellar Ataxia	Inherited ataxia that primarily affects the cerebellum and leads to problems with coordination and balance.
G12.0	Infantile Spinal Muscular Atrophy	Form of spinal muscular atrophy that begins in infancy and leads to muscle weakness and atrophy.
G13.0	Arsenic-Induced Polyneuropathy	Polyneuropathy caused by exposure to arsenic, leading to damage to peripheral nerves.
G10.2	Familial Creutzfeldt-Jakob Disease	A rare, inherited prion disease that causes rapidly progressive dementia and other neurological symptoms.
G11.4	Early-Onset Ataxia with Oculomotor Apraxia and Hypoalbuminemia	A rare inherited condition characterized by ataxia, oculomotor apraxia, and hypoalbuminemia.
G12.1	X-Linked Spinal Muscular Atrophy	A form of spinal muscular atrophy caused by a mutation on the X chromosome, typically affecting males.
G13.8	Other Systemic Atrophies Primarily Affecting the Central Nervous System	Systemic atrophies with central nervous system involvement that are not covered by more specific codes.
G11.9	Hereditary Ataxia, Unspecified	Unspecified hereditary ataxia, indicating a genetic disorder that affects coordination and balance.
G14.1	Postpolio Syndrome	Postpolio syndrome, which occurs in individuals who had polio and later experience new muscle weakness and fatigue.

ICD-10-CM Code G20-G26: Extrapyramidal and Movement Disorders

ICD-10-CM Code G20-G26 encompasses Extrapyramidal and Movement Disorders, a group of neurological conditions characterized by disturbances in motor control and involuntary movements. These disorders primarily affect the extrapyramidal system, a part of the brain responsible for regulating and modulating movement.

Key ICD-10-CM Codes for Extrapyramidal and Movement Disorders
ICD Code	Description	Diagnosis
G20	Parkinson's Disease	Parkinson's disease, a neurodegenerative disorder affecting motor control.
G21.1	Drug-Induced Parkinsonism	Secondary parkinsonism due to medications or drugs.
G24.1	Focal Dystonia	Focal dystonia is a movement disorder characterized by muscle contractions in specific body regions.
G25.0	Essential Tremor	Essential tremor, a common neurological disorder resulting in involuntary rhythmic shaking.
G25.2	Drug-Induced Tics and Tics Disorder	Tics or tic disorders triggered by medication or drugs.
G25.81	Restless Legs Syndrome	Restless legs syndrome or an irresistible urge to move the legs, often when at rest.
G25.9	Extrapyramidal and Movement Disorder, Unspecified	Unspecified extrapyramidal and movement disorder.
G23.1	Neuroacanthocytosis Syndrome	A rare genetic disorder involving movement abnormalities and abnormal red blood cell shape.
G24.3	Myoclonus	Characterized by sudden, brief muscle contractions.
G25.3	Tardive Dyskinesia	Tardive dyskinesia is a movement disorder often caused by long-term use of certain medications.

ICD-10-CM Code G30-G32: Other Degenerative Diseases of the Nervous System

Other Degenerative Diseases of the Nervous System is a category of neurological disorders primarily characterized by the progressive degeneration of nerve cells or tissues within the nervous system. The scope of this code range includes various conditions with different underlying causes and clinical manifestations.

Key ICD-10-CM Codes for Other Degenerative Diseases of the Nervous System
ICD Code	Description	Diagnosis
G30.9	Alzheimer's Disease, Unspecified	Unspecified Alzheimer's disease, typically involving cognitive decline and memory loss.
G31.0	Frontotemporal Dementia	A condition primarily affecting the frontal and temporal lobes of the brain, leading to changes in behavior, personality, and language difficulties.
G31.2	Degeneration of Nervous System Due to Alcohol	Degenerative nervous system disorders caused by chronic alcohol abuse.
G31.8	Other Specified Degenerative Diseases of the Nervous System	Other specific degenerative diseases that don't fall into more defined categories.
G31.83	Dementia with Lewy Bodies	Characterized by cognitive decline, visual hallucinations, and motor symptoms.
G31.89	Other Specified Degenerative Diseases of Nervous System	Other specific degenerative disorders not classified elsewhere.
G32.0	Subacute Combined Degeneration of Spinal Cord in Diseases Classified Elsewhere	Subacute combined degeneration of the spinal cord associated with vitamin B12 deficiency.
G32.1	Chronic Spongiform Encephalopathy	Chronic spongiform encephalopathy, a rare disorder characterized by sponge-like changes in brain tissue.
G32.81	Cerebellar Ataxia in Diseases Classified Elsewhere	Cerebellar ataxia associated with other underlying conditions.
G31.82	Mild Cognitive Impairment	A condition characterized by a cognitive decline that is more significant than expected for an individual's age but not severe enough to qualify as dementia.

‍

ICD-10-CM Code G35-G37: Demyelinating Diseases of the Central Nervous System

The scope of G35-G37 covers a range of disorders characterized by demyelination within the central nervous system. These conditions can have various causes, including autoimmune processes, viral infections, and other factors. Clinical symptoms can vary widely and may include weakness, sensory disturbances, visual problems, and cognitive deficits.

Key ICD-10-CM Codes for Demyelinating Diseases of the Central Nervous System
ICD Code	Description	Diagnosis
G35.1	Other Acute Disseminated Demyelination	Acute disseminated demyelination, including conditions like acute disseminated encephalomyelitis (ADEM)
G35.0	Multiple Sclerosis	A chronic autoimmune demyelinating disease that affects the central nervous system
G36.0	Acute Transverse Myelitis	Characterized by inflammation and demyelination of the spinal cord
G37.1	Neuromyelitis Optica	An autoimmune demyelinating disorder primarily affecting the optic nerves and spinal cord
G37.3	Central Demyelination of Corpus Callosum	Demyelination diagnosis affecting the corpus callosum, which connects the two hemispheres of the brain
G36.9	Central Demyelination, Unspecified	Central demyelination without a specified cause
G35.2	Balo's Concentric Sclerosis	A rare demyelinating disease characterized by concentric rings of demyelination
G36.8	Other Central Demyelination	Other central demyelinating conditions not classified elsewhere
G37.9	Demyelinating Disease of Central Nervous System, Unspecified	Demyelinating disease of the central nervous system without further specification
G37.0	Diffuse Cerebral Sclerosis	A rare condition characterized by widespread demyelination in the brain

ICD-10-CM Code G40-G47: Episodic and Paroxysmal Disorders

The ICD-10-CM Code G40-G47 category encompasses a range of episodic and paroxysmal disorders, characterized by sudden and recurrent episodes of abnormal bodily movements. These disorders affect the nervous system and can manifest as a variety of symptoms, often involving altered consciousness, muscle function, or sensory perception.

Key ICD-10-CM Codes for Episodic and Paroxysmal Disorders
ICD Code	Description	Diagnosis
G40.9	Epileptic Seizures, Unspecified	Used for cases of epileptic seizures when the specific type is not diagnosed
G41.0	Status Epilepticus	Designates a state of prolonged or repeated epileptic seizures without full recovery between them
G45.9	Transient Cerebral Ischemic Attack, Unspecified	Used when a transient cerebral ischemic attack doesn't fit into a more specific code category
G43.9	Migraine, Unspecified	This applies to migraine headaches, but the specific subtype is not determined
G44.209	Tension-Type Headache, Unspecified	Used for tension-type headaches when the exact subtype is not identified
G45.4	Transient Global Amnesia	Indicates a sudden, temporary episode of memory loss and disorientation
G46.4	Drug-Induced Hemiplegic Migraine, Not Intractable	For cases of hemiplegic migraine triggered by drug use but not classified as intractable
G47.00	Insomnia, Unspecified	Used for unspecified cases of insomnia, where the underlying cause or type is not identified
G47.10	Narcolepsy	This applies to patients diagnosed with narcolepsy, a disorder characterized by excessive daytime sleepiness
G47.31	Obstructive Sleep Apnea (Adult) (Pediatric)	Adult and pediatric cases of obstructive sleep apnea, a condition marked by recurrent interruptions in breathing during sleep

ICD-10-CM Code G50-G59: Nerve, Nerve Root, and Plexus Disorders

This category addresses disorders associated with the nervous system, specifically focusing on issues involving nerves, nerve roots, and plexuses. This classification is integral to the field of neurology and helps healthcare professionals diagnose and manage conditions related to these intricate neural networks.

Key ICD-10-CM Codes for Nerve, Nerve Root, and Plexus Disorders
ICD Code	Description	Diagnosis
G54.1	Nerve Root and Plexus Compression in Other Diseases	Used to denote nerve root or plexus compression caused by diseases other than disc disorders or other disorders of the intervertebral disc
G60.0	Hereditary Motor and Sensory Neuropathy	Applied to cases of hereditary neuropathies, which are inherited disorders affecting both motor and sensory nerves
G62.0	Drug-Induced Polyneuropathy	Used for polyneuropathy induced by medication or drug use
G62.9	Polyneuropathy, Unspecified	Indicates a general diagnosis of polyneuropathy when the specific cause or type is not identified
G63.0	Idiopathic Polyneuropathy	Used for cases of polyneuropathy where the cause is unknown or idiopathic
G54.0	Nerve Root and Plexus Compression in Disc Disorders of the Cervical Spine	Designates nerve root or plexus compression due to cervical disc disorders
G54.2	Nerve Root and Plexus Compression in Neoplastic Disease	Applied when nerve root or plexus compression is caused by a neoplastic disease, such as a tumor
G54.4	Nerve Root and Plexus Compression in Thoracic Outlet Syndrome	Used for cases where nerve roots or plexuses are compressed in the thoracic outlet, leading to symptoms like arm pain and numbness
G62.81	Other Drug-Induced Polyneuropathy	Designates polyneuropathy induced by specific drugs not covered by other drug-induced polyneuropathy codes
G63.2	Polyneuropathy Due to Other Toxic Agents	Used when polyneuropathy is caused by toxic agents other than drugs, such as exposure to environmental toxins

ICD-10-CM Code G60-G64: Disorders of the Peripheral Nervous System

The disorders within this ICD range affect the network of nerves that extend from the brain and spinal cord (the central nervous system) to various body parts, including the limbs, organs, and sensory organs. This classification is used to diagnose and document conditions related to peripheral nerve function.

Key ICD-10-CM Codes for Disorders of the Peripheral Nervous System
ICD Code	Description	Diagnosis
G61.0	Guillain-Barré Syndrome	An acute inflammatory disorder affecting the peripheral nerves and often resulting in muscle weakness or paralysis
G61.81	Chronic Inflammatory Demyelinating Polyneuropathy	Applied to chronic inflammatory demyelinating polyneuropathy (CIDP) cases, a disorder characterized by progressive weakness and impaired sensory function
G60.0	Hereditary Motor and Sensory Neuropathy	Used for diagnosing hereditary motor and sensory neuropathy, including conditions like Charcot-Marie-Tooth disease
G62.0	Drug-Induced Polyneuropathy	Designates polyneuropathy induced by medications or drug use
G54.0	Nerve Root and Plexus Compression in Disc Disorders of the Cervical Spine	Indicates nerve root or plexus compression due to cervical disc disorders
G54.2	Nerve Root and Plexus Compression in Neoplastic Disease	Used for cases where nerve root or plexus compression, caused by neoplastic diseases, such as tumors
G62.9	Polyneuropathy, Unspecified	This code is used for general diagnosis of polyneuropathy when the specific cause or type is not identified.
G57.10	Carpal Tunnel Syndrome, Unspecified Hand	Applied when a patient is diagnosed with carpal tunnel syndrome but the specific hand is not specified.
G57.12	Carpal Tunnel Syndrome, Left Hand	For cases where carpal tunnel syndrome is specifically diagnosed in the left hand.
G63.2	Polyneuropathy Due to Other Toxic Agents	Used when polyneuropathy is caused by toxic agents other than drugs, such as environmental toxins.

Further Reading:

ICD-10-CM Code G90-G99: Other Disorders of the Nervous System

This classification is a catch-all for various neurological disorders, and it helps healthcare professionals and medical coders accurately diagnose and document a broad array of conditions.

Key ICD-10-CM Codes for Other Disorders of the Nervous System
ICD Code	Description	Diagnosis
G90.9	Unspecified Disorder of the Nervous System	Used when the specific disorder affecting the nervous system is not identified or remains unspecified.
G91.0	Hydrocephalus	A condition characterized by the accumulation of excess cerebrospinal fluid in the brain, which can lead to increased intracranial pressure
G91.2	NPH (Normal Pressure Hydrocephalus)	A type of hydrocephalus characterized by gait disturbances, cognitive impairment, and urinary incontinence
G93.1	Anoxic Brain Damage, Not Elsewhere Classified	Designates anoxic brain damage resulting from oxygen deprivation, which can occur in various clinical scenarios.
G95.9	Other and Unspecified Diseases of Spinal Cord	A disorder affecting the spinal cord is present, but the specific diagnosis is not detailed
G96.0	Cerebrospinal Fluid Leak	Indicates the presence of cerebrospinal fluid leakage, often related to traumatic or iatrogenic causes.
G96.8	Other Disorders of Central Nervous System	Used for various disorders of the central nervous system not classified elsewhere
G97.0	Cerebral Spinal Fluid Leak Following Intracranial Surgery	Applied when cerebrospinal fluid leakage occurs as a complication following intracranial surgery
G97.1	Other Postprocedural Cerebrospinal Fluid Leak	Designates cerebrospinal fluid leakage that occurs as a result of a procedure other than intracranial surgery
G99.9	Other Disorder of Nervous System	Used for other neurological disorders affecting the nervous system when a specific diagnosis is not provided.

Conclusion

In the complex world of healthcare, ICD-10 codes play a pivotal role in accurately diagnosing and treating patients with nervous system diseases. From migraines to devastating conditions like ALS, these codes are a universal language for medical professionals, ensuring that patients receive the care they need.

We've barely scratched the surface of this intricate system. So, the next time you visit your healthcare provider, remember that behind those codes lies a world of knowledge and expertise.

‍

Disclaimer: The information provided in this blog regarding the International Classification of Diseases (ICD) codes is intended for informational purposes only. We strive to offer accurate and up-to-date content. However, the ICD codes are subject to changes, updates, and modifications by authoritative bodies such as the Centers for Disease Control and Prevention (CDC), the World Health Organization (WHO), and other relevant healthcare organizations. These changes can occur due to advancements in medical knowledge, new diseases, evolving diagnostic criteria, or updates in medical terminology.

Need some help? Talk to an Expert

Share this post

Practice Management