ICD10BillableValid for clinical use
ICD-10 Code E20.818: Other specified hypoparathyroidism due to impaired parathyroid hormone secretion
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Endocrine, nutritional and metabolic diseases (E00-E89).
šClinical overview
This ICD-10 code is commonly used when documentation describes hypoparathyroidism or a related parathyroid-hormone deficiency or resistance disorder. The most accurate code depends on whether the record identifies idiopathic, pseudo-, autoimmune, secondary, secretion-related, other specified, or unspecified hypoparathyroidism.
When is it used?
- May be used when a clinician documents other specified hypoparathyroidism due to impaired parathyroid hormone secretion in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code can be used as a clinically usable diagnosis entry in standardized coding workflows.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
š©ŗClinical context
When commonly used
- Endocrinology, primary-care, inpatient, and utilization-review workflows where hypocalcemia or parathyroid-hormone dysfunction is part of the active problem list.
- Coding workflows where the chart identifies the mechanism of hypoparathyroidism, such as hormone resistance, autoimmune disease, impaired secretion, or another specified endocrine context.
Common management context
- Evaluation often includes calcium, phosphorus, magnesium, vitamin D, and parathyroid hormone review, symptom assessment for tetany or paresthesias, and endocrine follow-up planning.
- Documentation usually becomes more specific when the chart identifies idiopathic versus pseudo- versus autoimmune versus secondary hypoparathyroidism, or clarifies impaired secretion versus another specified mechanism.
- Specialist context already linked on this page includes Endocrinologist, General Physician.
šKey distinctions
Important notes
- This ICD-10 family captures hypoparathyroidism and related parathyroid-hormone deficiency or resistance patterns rather than hyperparathyroidism or unrelated calcium-balance disorders.
- Mechanism detail, such as pseudo-, autoimmune, secondary, secretion-related, or unspecified pattern, drives the final code specificity inside this family.
- Hypoparathyroidism due to impaired parathyroid hormone secretion is coded separately from idiopathic, pseudo-, autoimmune, and broader other-specified hypoparathyroidism patterns.
- Other specified hypoparathyroidism is coded separately from idiopathic, pseudo-, autoimmune, secretion-related, and unspecified hypoparathyroidism patterns.
- Documentation that describes hypoparathyroidism is coded differently from hyperparathyroidism, vitamin-D disorders, or other endocrine causes of calcium imbalance.
Related codes to consider
E20.810Autosomal dominant hypocalcemia
Related hypoparathyroidism ICD-10 code; documentation often becomes more specific when the chart identifies idiopathic versus pseudo- versus autoimmune versus secondary pattern, impaired hormone secretion, or another endocrine context.
E20.811Secondary hypoparathyroidism in diseases classified elsewhere
Related hypoparathyroidism ICD-10 code; documentation often becomes more specific when the chart identifies idiopathic versus pseudo- versus autoimmune versus secondary pattern, impaired hormone secretion, or another endocrine context.
E20.812Autoimmune hypoparathyroidism
Related hypoparathyroidism ICD-10 code; documentation often becomes more specific when the chart identifies idiopathic versus pseudo- versus autoimmune versus secondary pattern, impaired hormone secretion, or another endocrine context.
E20.819Hypoparathyroidism due to impaired parathyroid hormone secretion, unspecified
Related hypoparathyroidism ICD-10 code; documentation often becomes more specific when the chart identifies idiopathic versus pseudo- versus autoimmune versus secondary pattern, impaired hormone secretion, or another endocrine context.
Code hierarchy
chapter
4Endocrine, nutritional and metabolic diseases (E00-E89)
block
E20-E35Disorders of other endocrine glands
category
E20Hypoparathyroidism
category
E20.8Other hypoparathyroidism
category
E20.81Hypoparathyroidism due to impaired parathyroid hormone secretion
currentE20.81
Official coding notes
Inclusion terms
- Familial isolated hypoparathyroidism
Where you may see this code
You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.
Related specialists
EndocrinologistGeneral Physician
Related codes
Sibling codes
Coverage-related procedures and services
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Source: CMS coverage guidance
Coding guidelines
Common synonyms
Other specified hypoparathyroidism due to impaired parathyroid hormone secretion
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.