ICD-10 Code for Myxedema
Also indexed as (adult) (idiocy) (infantile) (juvenile)
The ICD-10-CM code for myxedema is E03.9 — Hypothyroidism, unspecified. This is the code the Alphabetic Index gives for myxedema with no further qualifier, valid for FY2027 (October 1, 2026 – September 30, 2027).
E03.9 is billable but unspecified. If the documentation names a type, site or cause, one of the more specific codes below is likely expected.
Which myxedema code should you use?
The Alphabetic Index lists 6 codes under Myxedema. Which one applies depends on the qualifier documented in the record — the type, site, cause, or associated condition. Find the qualifier below, then verify the code in the Tabular List before using it.
By type
| circumscribed | E05.90 | Thyrotoxicosis, unspecified without thyrotoxic crisis or storm | |
| coma | E03.5 | Myxedema coma | |
| congenital | E00.1 | Congenital iodine-deficiency syndrome, myxedematous type | |
| cutis | L98.5 | Mucinosis of the skin | |
| localized | E05.90 | Thyrotoxicosis, unspecified without thyrotoxic crisis or storm | |
| papular | L98.5 | Mucinosis of the skin |
Myxedema circumscribed
| with storm | E05.91 | Thyrotoxicosis, unspecified with thyrotoxic crisis or storm |
Myxedema localized
| with storm | E05.91 | Thyrotoxicosis, unspecified with thyrotoxic crisis or storm |
Index terms and codes are reproduced from the official ICD-10-CM FY2027 release. The Alphabetic Index is a finding aid — a code must always be verified in the Tabular List before it is reported. Data sources