| Header | Description |
| G00* | Bacterial meningitis, not elsewhere classified |
| G03* | Meningitis due to other and unspecified causes |
| G04* | Encephalitis, myelitis and encephalomyelitis |
| G04.0* | Acute disseminated encephalitis and encephalomyelitis (ADEM) |
| G04.3* | Acute necrotizing hemorrhagic encephalopathy |
| G04.8* | Other encephalitis, myelitis and encephalomyelitis |
| G04.9* | Encephalitis, myelitis and encephalomyelitis, unspecified |
| G05* | Encephalitis, myelitis and encephalomyelitis in diseases classified elsewhere |
| G06* | Intracranial and intraspinal abscess and granuloma |
| G11* | Hereditary ataxia |
| G12* | Spinal muscular atrophy and related syndromes |
| G12.2* | Motor neuron disease |
| G13* | Systemic atrophies primarily affecting central nervous system in diseases classified elsewhere |
| G21* | Secondary parkinsonism |
| G21.1* | Other drug-induced secondary parkinsonism |
| G23* | Other degenerative diseases of basal ganglia |
| G24* | Dystonia |
| G24.0* | Drug induced dystonia |
| G25* | Other extrapyramidal and movement disorders |
| G25.6* | Drug induced tics and other tics of organic origin |
| G25.7* | Other and unspecified drug induced movement disorders |
| G25.8* | Other specified extrapyramidal and movement disorders |
| G30* | Alzheimer's disease |
| G31* | Other degenerative diseases of nervous system, not elsewhere classified |
| G31.0* | Frontotemporal dementia |
| G31.8* | Other specified degenerative diseases of nervous system |
| G32* | Other degenerative disorders of nervous system in diseases classified elsewhere |
| G32.8* | Other specified degenerative disorders of nervous system in diseases classified elsewhere |
| G36* | Other acute disseminated demyelination |
| G37* | Other demyelinating diseases of central nervous system |
| G40* | Epilepsy and recurrent seizures |
| G40.0* | Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset |
| G40.00* | Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable |
| G40.01* | Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, intractable |
| G40.1* | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures |
| G40.10* | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, not intractable |
| G40.11* | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures, intractable |
| G40.2* | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures |
| G40.20* | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, not intractable |
| G40.21* | Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with complex partial seizures, intractable |
| G40.3* | Generalized idiopathic epilepsy and epileptic syndromes |
| G40.30* | Generalized idiopathic epilepsy and epileptic syndromes, not intractable |
| G40.31* | Generalized idiopathic epilepsy and epileptic syndromes, intractable |
| G40.A* | Absence epileptic syndrome |
| G40.A0* | Absence epileptic syndrome, not intractable |
| G40.A1* | Absence epileptic syndrome, intractable |
| G40.B* | Juvenile myoclonic epilepsy [impulsive petit mal] |
| G40.B0* | Juvenile myoclonic epilepsy, not intractable |
| G40.B1* | Juvenile myoclonic epilepsy, intractable |
| G40.4* | Other generalized epilepsy and epileptic syndromes |
| G40.40* | Other generalized epilepsy and epileptic syndromes, not intractable |
| G40.41* | Other generalized epilepsy and epileptic syndromes, intractable |
| G40.5* | Epileptic seizures related to external causes |
| G40.50* | Epileptic seizures related to external causes, not intractable |
| G40.8* | Other epilepsy and recurrent seizures |
| G40.80* | Other epilepsy |
| G40.81* | Lennox-Gastaut syndrome |
| G40.82* | Epileptic spasms |
| G40.9* | Epilepsy, unspecified |
| G40.90* | Epilepsy, unspecified, not intractable |
| G40.91* | Epilepsy, unspecified, intractable |
| G43* | Migraine |
| G43.0* | Migraine without aura |
| G43.00* | Migraine without aura, not intractable |
| G43.01* | Migraine without aura, intractable |
| G43.1* | Migraine with aura |
| G43.10* | Migraine with aura, not intractable |
| G43.11* | Migraine with aura, intractable |
| G43.4* | Hemiplegic migraine |
| G43.40* | Hemiplegic migraine, not intractable |
| G43.41* | Hemiplegic migraine, intractable |
| G43.5* | Persistent migraine aura without cerebral infarction |
| G43.50* | Persistent migraine aura without cerebral infarction, not intractable |
| G43.51* | Persistent migraine aura without cerebral infarction, intractable |
| G43.6* | Persistent migraine aura with cerebral infarction |
| G43.60* | Persistent migraine aura with cerebral infarction, not intractable |
| G43.61* | Persistent migraine aura with cerebral infarction, intractable |
| G43.7* | Chronic migraine without aura |
| G43.70* | Chronic migraine without aura, not intractable |
| G43.71* | Chronic migraine without aura, intractable |
| G43.A* | Cyclical vomiting |
| G43.B* | Ophthalmoplegic migraine |
| G43.C* | Periodic headache syndromes in child or adult |
| G43.D* | Abdominal migraine |
| G43.8* | Other migraine |
| G43.80* | Other migraine, not intractable |
| G43.81* | Other migraine, intractable |
| G43.82* | Menstrual migraine, not intractable |
| G43.83* | Menstrual migraine, intractable |
| G43.9* | Migraine, unspecified |
| G43.90* | Migraine, unspecified, not intractable |
| G43.91* | Migraine, unspecified, intractable |
| G44* | Other headache syndromes |
| G44.0* | Cluster headaches and other trigeminal autonomic cephalgias (TAC) |
| G44.00* | Cluster headache syndrome, unspecified |
| G44.01* | Episodic cluster headache |
| G44.02* | Chronic cluster headache |
| G44.03* | Episodic paroxysmal hemicrania |
| G44.04* | Chronic paroxysmal hemicrania |
| G44.05* | Short lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) |
| G44.09* | Other trigeminal autonomic cephalgias (TAC) |
| G44.2* | Tension-type headache |
| G44.20* | Tension-type headache, unspecified |
| G44.21* | Episodic tension-type headache |
| G44.22* | Chronic tension-type headache |
| G44.3* | Post-traumatic headache |
| G44.30* | Post-traumatic headache, unspecified |
| G44.31* | Acute post-traumatic headache |
| G44.32* | Chronic post-traumatic headache |
| G44.4* | Drug-induced headache, not elsewhere classified |
| G44.5* | Complicated headache syndromes |
| G44.8* | Other specified headache syndromes |
| G45* | Transient cerebral ischemic attacks and related syndromes |
| G46* | Vascular syndromes of brain in cerebrovascular diseases |
| G47* | Sleep disorders |
| G47.0* | Insomnia |
| G47.1* | Hypersomnia |
| G47.2* | Circadian rhythm sleep disorders |
| G47.3* | Sleep apnea |
| G47.4* | Narcolepsy and cataplexy |
| G47.41* | Narcolepsy |
| G47.42* | Narcolepsy in conditions classified elsewhere |
| G47.5* | Parasomnia |
| G47.6* | Sleep related movement disorders |
| G50* | Disorders of trigeminal nerve |
| G51* | Facial nerve disorders |
| G51.3* | Clonic hemifacial spasm |
| G52* | Disorders of other cranial nerves |
| G54* | Nerve root and plexus disorders |
| G56* | Mononeuropathies of upper limb |
| G56.0* | Carpal tunnel syndrome |
| G56.1* | Other lesions of median nerve |
| G56.2* | Lesion of ulnar nerve |
| G56.3* | Lesion of radial nerve |
| G56.4* | Causalgia of upper limb |
| G56.8* | Other specified mononeuropathies of upper limb |
| G56.9* | Unspecified mononeuropathy of upper limb |
| G57* | Mononeuropathies of lower limb |
| G57.0* | Lesion of sciatic nerve |
| G57.1* | Meralgia paresthetica |
| G57.2* | Lesion of femoral nerve |
| G57.3* | Lesion of lateral popliteal nerve |
| G57.4* | Lesion of medial popliteal nerve |
| G57.5* | Tarsal tunnel syndrome |
| G57.6* | Lesion of plantar nerve |
| G57.7* | Causalgia of lower limb |
| G57.8* | Other specified mononeuropathies of lower limb |
| G57.9* | Unspecified mononeuropathy of lower limb |
| G58* | Other mononeuropathies |
| G60* | Hereditary and idiopathic neuropathy |
| G61* | Inflammatory polyneuropathy |
| G61.8* | Other inflammatory polyneuropathies |
| G62* | Other and unspecified polyneuropathies |
| G62.8* | Other specified polyneuropathies |
| G65* | Sequelae of inflammatory and toxic polyneuropathies |
| G70* | Myasthenia gravis and other myoneural disorders |
| G70.0* | Myasthenia gravis |
| G70.8* | Other specified myoneural disorders |
| G71* | Primary disorders of muscles |
| G71.0* | Muscular dystrophy |
| G71.1* | Myotonic disorders |
| G72* | Other and unspecified myopathies |
| G72.4* | Inflammatory and immune myopathies, not elsewhere classified |
| G72.8* | Other specified myopathies |
| G73* | Disorders of myoneural junction and muscle in diseases classified elsewhere |
| G80* | Cerebral palsy |
| G81* | Hemiplegia and hemiparesis |
| G81.0* | Flaccid hemiplegia |
| G81.1* | Spastic hemiplegia |
| G81.9* | Hemiplegia, unspecified |
| G82* | Paraplegia (paraparesis) and quadriplegia (quadriparesis) |
| G82.2* | Paraplegia |
| G82.5* | Quadriplegia |
| G83* | Other paralytic syndromes |
| G83.1* | Monoplegia of lower limb |
| G83.2* | Monoplegia of upper limb |
| G83.3* | Monoplegia, unspecified |
| G83.8* | Other specified paralytic syndromes |
| G89* | Pain, not elsewhere classified |
| G89.1* | Acute pain, not elsewhere classified |
| G89.2* | Chronic pain, not elsewhere classified |
| G90* | Disorders of autonomic nervous system |
| G90.0* | Idiopathic peripheral autonomic neuropathy |
| G90.5* | Complex regional pain syndrome I (CRPS I) |
| G90.51* | Complex regional pain syndrome I of upper limb |
| G90.52* | Complex regional pain syndrome I of lower limb |
| G91* | Hydrocephalus |
| G93* | Other disorders of brain |
| G93.4* | Other and unspecified encephalopathy |
| G93.8* | Other specified disorders of brain |
| G95* | Other and unspecified diseases of spinal cord |
| G95.1* | Vascular myelopathies |
| G95.2* | Other and unspecified cord compression |
| G95.8* | Other specified diseases of spinal cord |
| G96* | Other disorders of central nervous system |
| G96.1* | Disorders of meninges, not elsewhere classified |
| G97* | Intraoperative and postprocedural complications and disorders of nervous system, not elsewhere classified |
| G97.3* | Intraoperative hemorrhage and hematoma of a nervous system organ or structure complicating a procedure |
| G97.4* | Accidental puncture and laceration of a nervous system organ or structure during a procedure |
| G97.5* | Postprocedural hemorrhage of a nervous system organ or structure following a procedure |
| G97.6* | Postprocedural hematoma and seroma of a nervous system organ or structure following a procedure |
| G97.8* | Other intraoperative and postprocedural complications and disorders of nervous system |
| G98* | Other disorders of nervous system not elsewhere classified |
| G99* | Other disorders of nervous system in diseases classified elsewhere |
