H42 — Glaucoma in diseases classified elsewhere
Is H42 billable?
Yes — H42 is billable for FY2027. H42 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. H42 may be submitted for encounters from October 1, 2026 through September 30, 2027.
H42 at a glance
| Code | H42 |
|---|---|
| Description | Glaucoma in diseases classified elsewhere |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
What Medicare edits apply to H42?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name H42 directly.
This code describes a manifestation of an underlying disease. The underlying condition must be sequenced before it, so it can never be the principal or first-listed diagnosis.
Which MS-DRGs does H42 group to?
H42 sits in MDC 02 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 124Other Disorders of the Eye with MCC or Thrombolytic Agentmedical
- 125Other Disorders of the Eye without MCCmedical
How is H42 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to H42. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Glaucoma › in › amyloidosis
- Glaucoma › in › aniridia
- Glaucoma › in › endocrine disease NOS
- Glaucoma › in › Lowe's syndrome
- Glaucoma › in › metabolic disease NOS
- Glaucoma › in › Rieger anomaly
Excludes1 — never code together
The conditions below can never be reported together with H42 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Code first
The underlying condition below must be sequenced before H42. H42 describes a manifestation and cannot be the principal or first-listed diagnosis.
Excludes2 — not included here — inherited from Chapter 7
The conditions below are not part of H42, but a patient may have both at the same time. When documentation supports it, H42 and the excluded code may both be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- diabetes mellitus related eye conditions (E09.3-, E10.3-, E11.3-, E13.3-)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury (trauma) of eye and orbit (S05.-)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
- syphilis related eye disorders (A50.01, A50.3-, A51.43, A52.71)
How long has H42 existed?
H42 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
Which codes are confused with H42?
ICD-10-CM declares these codes mutually exclusive with H42 — exactly one of each pair can be correct for a given encounter.