Is G35.C1 a billable ICD-10-CM code?

Yes. G35.C1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does G35.C1 sit in the tabular list?

Diseases of the nervous system (G00-G99), in the block Demyelinating diseases of the central nervous system (G35-G37).

G35.C1

G35.C1 — Active secondary progressive multiple sclerosis

Billable / specific codeICD-10-CM

G35.C1 is a billable, specific ICD-10-CM code for active secondary progressive multiple sclerosis. It is valid for submission on a claim.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

Secondary progressive multiple sclerosis with evidence of inflammatory disease activity

Risk adjustment

G35.C1 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:

HCC 198 Multiple Sclerosis0.647 RAF

Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.

Medicare coverage

G35.C1 is named in 68 Medicare coverage policies — 67 listing it as supporting medical necessity, and 1 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A56845Billing and Coding: Venous Angioplasty with or without Stent Placement for the Treatment of Chronic Cerebrospinal Venous Insufficiencynot covered
A52465Knee Orthoses - Policy Article
A52494High Frequency Chest Wall Oscillation Devices - Policy Article
A52510Mechanical In-exsufflation Devices - Policy Article

How G35.C1 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to G35.C1.

Sclerosis, sclerotic›multiple›progressive›secondary›active
Sclerosis, sclerotic›multiple›progressive›secondary›with›evidence of inflammatory disease activity

Related codes at this level

Codes that share G35.C. If G35.C1 is not quite right, the correct code is usually one of these.

Questions about G35.C1

Is G35.C1 a billable ICD-10-CM code?: Yes. G35.C1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does G35.C1 sit in the tabular list?: Diseases of the nervous system (G00-G99), in the block Demyelinating diseases of the central nervous system (G35-G37).