ICD-10 Code E20.818 – Other specified hypoparathyroidism due to impaired parathyroid hormone secretion (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E20.818 – Other specified hypoparathyroidism due to impaired parathyroid hormone secretion
What it is
This code identifies hypoparathyroidism caused by reduced parathyroid hormone secretion when the documentation specifies another, more exact cause not captured by a different code.
Clinical signs
Clinical features vary; refer to documentation. Common findings in hypoparathyroidism include neuromuscular irritability, tingling, muscle cramps, and signs consistent with low parathyroid hormone activity.
When to use this code
Use E20.818 when the provider documents hypoparathyroidism due to impaired parathyroid hormone secretion and also specifies that it is “other specified” rather than primary, postsurgical, or another listed type. Apply it to confirmed diagnoses, not to a rule-out condition. If the record is unclear, check documentation.
Do not use for
Do not use this code for postsurgical hypoparathyroidism, hypocalcemia without documented hypoparathyroidism, or cases where the cause is not specified. Check documentation.
Coding tip
Match the code to the exact provider wording, especially the phrase “other specified” and the documented cause of impaired secretion.