What is ICD-10 code E13.649?

E13.649 is the ICD-10-CM diagnosis code for Other specified diabetes mellitus with hypoglycemia without coma. A type of diabetes (not type 1 or type 2) with low blood sugar that does not cause loss of consciousness. E13.649 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. E13.649 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. E13.649 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. E13.649 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Which HCC does E13.649 map to under V28?

E13.649 maps to CMS-HCC V28 HCC 38 (Diabetes with No, Glycemic, or Unspecified Complications). The category numbers, labels, and conditions come from the CMS-HCC V28 model file for payment year 2026.

2026 ICD-10-CM E13.649: Other specified diabetes

E13.649 maps to CMS-HCC V28 38. A source-labeled RAF reference is available. Confirm the documented diagnosis and applicable coding requirements. MEAT criteria · RAF Calculator · HCC Buddy coding tools

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Code lookupE13.649

Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Endocrine, nutritional and metabolic diseases (E00-E89) / Diabetes mellitus (E08-E13)

E13.649

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Other specified diabetes mellitus with hypoglycemia without coma

A type of diabetes (not type 1 or type 2) with low blood sugar that does not cause loss of consciousness.

Buddy Insight

E13.

Overview Risk Models Code Book Documentation Audit Notes Edition comparison

CMS-HCC V28

Mapped

HCC 38

Diabetes with No, Glycemic, o...

Code-level coefficient reference

CMS-HCC V24

Historical

Not used for standard CY2026 Medicare Advantage payment. Select a historical period to review V24.

Not used for CY2026 payment

ACA/HHS

Mapped

HCC 021

HHS-HCC 021 adult, RAF varies...

Code-level coefficient reference

ESRD/PACE

Mapped

HCC 18

Diabetes with Chronic Complic...

Code-level coefficient reference

RXHCC

Mapped

HCC 30

Diabetes with Complications

Code-level coefficient reference

Code Book Path

Official

E13.6Other specified diabetes mellitus with other specified complications E13.64Other specified diabetes mellitus with hypoglycemia E13.649Other specified diabetes mellitus with hypoglycemia without coma

Inclusion Terms

Official

No inclusion terms are included in this display for E13.649. Check the code and parent instructions in the Code Book.

Excludes 2

Official

No Excludes 2 notes are included in this display for E13.649. Check the code and parent instructions in the Code Book.

Related Codes

Official

E13.641Other specified diabetes mellitus with hypoglycemia with coma

Includes

Official

diabetes mellitus due to genetic defects of beta-cell functionInherited from E13
diabetes mellitus due to genetic defects in insulin actionInherited from E13
postpancreatectomy diabetes mellitusInherited from E13
postprocedural diabetes mellitusInherited from E13
secondary diabetes mellitus NECInherited from E13

Excludes 1

Official

transitory endocrine and metabolic disorders specific to newborn (P70-P74)Inherited from E00-E89, E13
diabetes (mellitus) due to autoimmune process (E10.-)Inherited from E00-E89, E13
diabetes (mellitus) due to immune mediated pancreatic islet beta-cell destruction (E10.-)Inherited from E00-E89, E13
diabetes mellitus due to underlying condition (E08.-)Inherited from E00-E89, E13
drug or chemical induced diabetes mellitus (E09.-)Inherited from E00-E89, E13
gestational diabetes (O24.4-)Inherited from E00-E89, E13
neonatal diabetes mellitus (P70.2)Inherited from E00-E89, E13
type 1 diabetes mellitus (E10.-)Inherited from E00-E89, E13

Code First

Official

No Code First sequencing instructions are included in this display for E13.649. Check the code and parent instructions in the Code Book.

Use Additional

Official

code to identify control using:Inherited from E13, E13.64
injectable non-insulin antidiabetic drugs (Z79.85)Inherited from E13, E13.64
insulin (Z79.4)Inherited from E13, E13.64
oral antidiabetic drugs (Z79.84)Inherited from E13, E13.64
oral hypoglycemic drugs (Z79.84)Inherited from E13, E13.64
code for hypoglycemia level, if applicable (E16.A-)Inherited from E13, E13.64

Code Also

Official

No Code Also instructions are included in this display for E13.649. Check the code and parent instructions in the Code Book.

Buddy Documentation Tip

HCC Buddy guidance

The provider must document secondary diabetes, the hypoglycemic episode, and confirm that coma did not occur.

Blood glucose levels, symptoms, precipitating factors, treatment, and any medication adjustments should be recorded.

MEAT Support

HCC Buddy guidance

The provider must document secondary diabetes, the hypoglycemic episode, and confirm that coma did not occur.

Blood glucose levels, symptoms, precipitating factors, treatment, and any medication adjustments should be recorded.

Audit Caution

HCC Buddy guidance

Do not confuse hypoglycemia (low blood sugar) with hyperglycemia (high blood sugar).

Ensure the episode is documented as occurring in the setting of secondary diabetes.

If the hypoglycemia is clearly drug-induced, consider whether E16.0 is more appropriate.

Common Mistakes

HCC Buddy guidance

E13.641 (hypoglycemia with coma) when consciousness is lost

E13.65 (hyperglycemia) for elevated blood sugar

E16.0-E16.2 (drug-induced or other hypoglycemia) for non-diabetic hypoglycemia causes.

Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →

Is E13.649 an HCC code?

Yes. E13.649 (Other specified diabetes mellitus with hypoglycemia without coma) maps to HCC 38, Diabetes with No, Glycemic, or Unspecified Complications under the CMS-HCC V28 risk adjustment model, with a source-labeled community non-dual aged reference coefficient of 0.166. Source-labeled code-level coefficients are references, not member totals. Actual contribution depends on complete member context, hierarchy and cleanup rules, interactions, and model year. HCC Buddy's RAF Calculator supports CMS-HCC V28 PY2026 and shows no score unless every required source and calculation check passes. It is billable for payment year 2026.

Coder answer: E13.649 is billable and maps to V28 HCC 38, Diabetes with No, Glycemic, or Unspecified Complications. Open it in the Code Book for the tabular path, RAF, and MEAT checklist.

Code: E13.649
Description: Other specified diabetes mellitus with hypoglycemia without coma
HCC (V28): HCC 38 — Diabetes with No, Glycemic, or Unspecified Complications
RAF reference coefficient: 0.166
Billable: Yes
Payment year: 2026

HCC Category Mapping

V28HCC 38, Diabetes with No, Glycemic, or Unspecified Complications

0.166

ESRDHCC 18, Diabetes with Chronic Complications

Not separately weighted

RxHCCHCC 30, Diabetes with Complications

Not separately weighted

These are source-labeled model coefficients, not member totals. A category may still be removed by hierarchy or model cleanup rules. Weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. Actual per-patient RAF contribution depends on member context, hierarchy and cleanup rules, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains available for historical review.

Work E13.649 in the Code Book — tabular path, V28 RAF reference, and MEAT checklist →

MEAT review for E13.649

For E13.649, confirm that the documentation supports the diagnosis and meets the applicable coding, encounter, program and payer requirements. MEAT (Monitor, Evaluate, Assess, or Treat) is a review mnemonic, not a universal CMS coding rule.

MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
EEvaluate: test results, medication response, or physical findings reviewed by the provider
AAssess: explicit mention in the assessment or plan with acknowledgment of status
TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Coder workflow notes

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What This Code Means

E13.649 is the ICD-10-CM diagnosis code for other specified diabetes mellitus with hypoglycemia without coma. A type of diabetes (not type 1 or type 2) with low blood sugar that does not cause loss of consciousness. E13.649 sits in the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89), within the section covering diabetes mellitus (e08-e13).

Under the CMS-HCC V28 risk adjustment model, E13.649 maps to Diabetes with No, Glycemic, or Unspecified Complications (HCC 38) with a source-labeled community, non-dual, aged reference coefficient of 0.166. No V24 mapping is shown for E13.649; use the applicable model and payment year when reviewing the V28 mapping. For CY2026 non-PACE Medicare Advantage, CMS uses 100% of the 2024 CMS-HCC model (V28). PACE uses a separate model blend. Source-labeled code-level coefficients are references, not member totals. Actual contribution depends on complete member context, hierarchy and cleanup rules, interactions, and model year. HCC Buddy's RAF Calculator supports CMS-HCC V28 PY2026 and shows no score unless every required source and calculation check passes.

Verify that hypoglycemia is present but the patient did not lose consciousness; if coma occurred, use E13.641 instead. For E13.649, confirm that the documentation supports the diagnosis and meets the applicable coding, encounter, program and payer requirements. MEAT (Monitor, Evaluate, Assess, or Treat) is a review mnemonic, not a universal CMS coding rule. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.

HCC Buddy maintains structured V28 and V24 mapping, source-labeled coefficient references, and MEAT documentation criteria for E13.649 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Verify that hypoglycemia is present but the patient did not lose consciousness; if coma occurred, use E13.641 instead
•Document the severity and symptoms of the hypoglycemic episode

Clinical Significance

E13.649 captures hypoglycemia without coma in other specified diabetes mellitus. Hypoglycemic episodes, while not resulting in loss of consciousness, can cause significant symptoms including confusion, diaphoresis, tremors, palpitations, and seizures. Recurrent hypoglycemia may lead to hypoglycemia unawareness, paradoxically increasing the risk of severe future episodes.

Documentation Requirements

✓The provider must document secondary diabetes, the hypoglycemic episode, and confirm that coma did not occur.
✓Blood glucose levels, symptoms, precipitating factors, treatment, and any medication adjustments should be recorded.

Commonly Confused Codes

•E13.641 (hypoglycemia with coma) when consciousness is lost
•E13.65 (hyperglycemia) for elevated blood sugar
•E16.0-E16.2 (drug-induced or other hypoglycemia) for non-diabetic hypoglycemia causes.