2026 ICD-10-CM Diagnosis Code E10.641Type 1 diabetes mellitus with hypoglycemia with coma
ICD-10-CM Codes›E00–E89›E08-E13›E10
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Risk Adjusts — HCC 36
- Chronic Condition
E10.641 is a billable ICD-10-CM diagnosis code for type 1 diabetes mellitus with hypoglycemia with coma. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 8, 10, 19, 637 through 639. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 355 closely related codes. Coders also document this condition as hypoglycemia due to type 1 diabetes mellitus. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Coma; stupor; and brain damage; Diabetes mellitus with complication; and Diabetes mellitus, Type 1.
For Medicare Advantage risk adjustment, E10.641 maps to CMS-HCC Category 36 (Diabetes with Severe Acute Complications) under the V28 model, adding a risk factor of about 0.166 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Quality Payment Program MeasuresBilling
Medicare quality measures that can apply when E10.641 is part of the patient record.
Diabetes: Hemoglobin A1c (HbA1c) Poor Control (>9%)
High Priority: YES
Measure Type: Intermediateoutcome
Submission Methods: Claims, Electronic Health Record, Cms Web Interface, Registry
Description: Percentage of patients 18-75 years of age with diabetes who had hemoglobin A1c > 9.0% during the measurement period.
Medicare Risk Adjustment (HCC)Billing
E10.641 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2026.
Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Hypoglycemia due to type 1 diabetes mellitus
- Hypoglycemic coma due to diabetes mellitus
- Hypoglycemic coma due to type 1 diabetes mellitus
Coding GuidelinesGuidance
The diabetes mellitus codes are combination codes that include the type of diabetes mellitus, the body system affected, and the complications affecting that body system. As many codes within a particular category as are necessary to describe all of the complications of the disease may be used. They should be sequenced based on the reason for a particular encounter. Assign as many codes from categories E08 - E13 as needed to identify all of the associated conditions that the patient has.
The age of a patient is not the sole determining factor, though most type 1 diabetics develop the condition before reaching puberty. For this reason type 1 diabetes mellitus is also referred to as juvenile diabetes.
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Coma
A coma is a deep state of unconsciousness. An individual in a coma is alive but unable to move or respond to his or her environment. Coma may occur as a complication of an underlying illness, or as a result of injuries, such as brain injury.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert E10.641 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About E10.641Overview
What is the ICD-10 code for type 1 diabetes mellitus with hypoglycemia with coma?
The ICD-10-CM code for type 1 diabetes mellitus with hypoglycemia with coma is E10.641 (sometimes written as E10641). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is E10.641 (Type 1 diabetes mellitus with hypoglycemia) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report type 1 diabetes mellitus with hypoglycemia with coma on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does E10.641 group to?
When type 1 diabetes mellitus with hypoglycemia with coma is the principal diagnosis on an inpatient stay, it groups to MS-DRG 8, 10, 19, 637, 638, 639, with relative weights from 0.6212 to 6.6272 depending on complications. Higher weights mean higher Medicare reimbursement.
Is E10.641 a CC or MCC?
CMS lists E10.641 as an MCC (major complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 355 closely related codes in its exclusion list.
What is the ICD-9 equivalent of E10.641?
Under the General Equivalence Mappings, type 1 diabetes mellitus with hypoglycemia with coma converts to ICD-9-CM 250.31 (DMI o cm nt st uncntrld). The mapping is approximate, so confirm the match fits the documentation.
What HCC is E10.641?
E10.641 (type 1 diabetes mellitus with hypoglycemia with coma) maps to CMS-HCC Category 36 (Diabetes with Severe Acute Complications), commonly written as HCC 36, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 17 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 30.
Does E10.641 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, E10.641 adds a risk adjustment factor of about 0.166 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.166 to 0.280 depending on the payment segment). A more severe related category (HCC 35) supersedes it when both are reported. See the full factor table on the HCC 36 category page.
