Crystal's MCW Coder Hub🧬 ICD-10-CM H40.61X1 — Glaucoma Secondary to Drugs, Right Eye, Mild Stage
Billable Code Confirmed — 7 Characters Complete
Non-Billable Parent Codes — Do Not Submit
- ❌
H40.61— 5-character — non-billable header; missing X placeholder + stage- ❌
H40.6— 4-character — non-billable subcategory header- ❌
H40— 3-character — category only — never billable
🚨 MANDATORY ADDITIONAL CODE — T-Code Is NOT Optional
ICD-10-CM contains an explicit “Use additional code” instruction at the H40.6 parent level: “Use additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)”
The T-code identifying the specific causative drug must accompany H40.61X1 on every claim and encounter. The most common pairing is:
- T38.0X5A — Adverse effect of glucocorticoids and synthetic analogues, initial encounter
- T38.0X5D — Adverse effect of glucocorticoids, subsequent encounter
- T38.0X5S — Adverse effect of glucocorticoids, sequela
Submitting H40.61X1 without the T-code is a coding compliance error and may trigger claim edits.
🔍 Code Description
ICD-10 CM H40.61X1 classifies glaucoma secondary to drug therapy, right eye, at the mild stage — a form of secondary open-angle glaucoma in which a pharmacologic agent, most commonly a corticosteroid, causes elevated intraocular pressure (IOP) that progresses to clinically documented glaucomatous optic nerve damage and/or visual field loss.
This is the coding home for steroid-induced glaucoma (SIG) — one of the most clinically important drug-related ocular complications in ophthalmologic practice. At the mild stage, the patient has confirmed glaucomatous optic nerve changes (cup-to-disc ratio enlargement, nerve fiber layer thinning on OCT) with early but measurable visual field loss — early paracentral scotomas or nasal step defects on Humphrey visual field — while central visual acuity remains largely intact. The mild stage designation reflects structural damage confirmed beyond the glaucoma suspect threshold; this is true glaucoma, not just elevated IOP (ocular hypertension).
📐 Understanding the X Placeholder — Why H40.61X1 Is Valid When H40.11X3 Was Not
This is a distinction worth putting in the vault permanently because it trips up coders constantly:
| Code | Status | Why |
|---|---|---|
| ❌ DELETED 2016 | X was a placeholder before laterality was added to H40.11; restructured to H40.1113 | |
| H40.61X1 | ✅ CURRENT + VALID | X is a required structural placeholder in position 6; H40.6x STILL uses this structure |
The X in H40.61X1 Is Structural — Not a Missing Character
The H40.6x secondary glaucoma family uses a 5-character stem with laterality (H40.61 = right, H40.62 = left, H40.63 = bilateral) followed by a required X placeholder in position 6, then the stage digit in position 7.
This differs from H40.11x (primary open-angle glaucoma) which was RESTRUCTURED in 2016 to embed laterality + stage into positions 5-8 without an X placeholder.
The rule of thumb: when the ICD-10-CM tabular instructs you to assign a 7th character and the stem is only 5 characters, the X fills position 6 as a required placeholder. This applies consistently across H40.3x (trauma), H40.4x (inflammation), H40.5x (other eye disorders), and H40.6x (drugs).
🌳 Code Tree / Hierarchy
H40.6 Glaucoma Secondary to Drugs ❌ Non-billable
│ Use additional code: T36-T50 (5th/6th char = 5)
│
├── H40.60 Unspecified eye ❌ Non-billable header
│ ├── H40.60X0 Stage unspecified
│ ├── H40.60X1 Mild stage
│ ├── H40.60X2 Moderate stage
│ ├── H40.60X3 Severe stage
│ └── H40.60X4 Indeterminate stage
│
├── H40.61 Right eye ❌ Non-billable header
│ ├── H40.61X0 Stage unspecified ⚠️ query
│ ├── H40.61X1 Mild stage ← THIS CODE ✅
│ ├── H40.61X2 Moderate stage
│ ├── H40.61X3 Severe stage
│ └── H40.61X4 Indeterminate stage
│
├── H40.62 Left eye ❌ Non-billable header
│ ├── H40.62X1 Mild stage ✅
│ ├── H40.62X2 Moderate stage ✅
│ ├── H40.62X3 Severe stage ✅
│ └── H40.62X4 Indeterminate stage ✅
│
└── H40.63 Bilateral ❌ Non-billable header
├── H40.63X1 Mild stage ✅
├── H40.63X2 Moderate stage ✅
└── H40.63X3 Severe stage ✅
📊 Glaucoma Stage Definitions — 7th Character Guide
| 7th Char | Stage | Visual Field Criteria (HVF 24-2) | C/D Ratio / RNFL | When to Use |
|---|---|---|---|---|
| 0 | Unspecified | Not documented | Not documented | ⚠️ Last resort — CDI query for stage |
| 1 | Mild ← This code | Mean deviation (MD) better than -6 dB; early field loss (paracentral scotoma, nasal step) not affecting central 5° | Enlarged C/D; early RNFL thinning on OCT | Documented early field loss, preserved central vision |
| 2 | Moderate | MD -6 to -12 dB; field loss respects horizontal meridian; not within 5° of fixation in both hemifields | Moderate RNFL thinning | Documented moderate field loss |
| 3 | Severe | MD worse than -12 dB; field loss within 5° of fixation in at least one hemifield | Significant RNFL loss; advanced cupping | Documented severe field loss |
| 4 | Indeterminate | Cannot be determined — media opacity, unreliable fields, patient unable to perform | Cannot be assessed | Media opacity; unreliable testing; patient unable to cooperate |
Mild Stage = MD Better Than -6 dB — Know This Threshold
The -6 dB mean deviation cutoff is the ICD-10-CM-aligned dividing line between mild and moderate glaucoma, based on the Hodapp-Parrish-Anderson criteria that underpin ICD-10-CM glaucoma staging. In plain language: mild stage means the patient has detectable but limited visual field loss that does not yet threaten central fixation. At H40.61X1 (mild stage), the patient likely still has good functional vision — the damage is real but early. This staging has direct implications for:
- Anti-glaucoma medication intensity (one drop vs. combination)
- Surgical threshold (SLT, MIGS, trabeculectomy considerations)
- Monitoring frequency (mild = every 6-12 months HVF; moderate/severe = every 3-6 months)
- Disability and functional documentation at follow-up
🔬 Pathophysiology — Steroid-Induced Glaucoma
Corticosteroids are the overwhelmingly most common cause of H40.61X1 in clinical practice. Understanding the mechanism drives both the clinical management AND the coding accuracy for the T-code selection:
How Steroids Cause Glaucoma
Glucocorticoid receptors are present on trabecular meshwork (TM) cells. When steroids bind these receptors, a cascade of structural changes occurs in the TM:
- Cross-linking of actin fiber networks → increased TM rigidity
- Deposition of fibronectin and collagen in the juxtacanalicular region → physical outflow obstruction
- Decreased metalloproteinase activity → impaired extracellular matrix turnover
- Reduced TM cellularity → less phagocytic clearance of debris
Net effect: aqueous outflow resistance increases → IOP rises. If IOP elevation is sustained and of sufficient magnitude, optic nerve damage progresses → glaucoma.
”Steroid Responder” Concept
Not all patients develop IOP elevation from steroids — susceptibility is genetically mediated.
| Response Category | IOP Increase After Topical Steroids | Clinical Action |
|---|---|---|
| Non-responder (~66%) | <6 mmHg increase | Routine monitoring |
| Low responder (~29%) | 6-15 mmHg increase | Monitor more closely; consider steroid-sparing agents |
| High responder (~5%) | >15 mmHg increase | High risk of SIG — switch to non-steroid or add IOP-lowering treatment |
Pre-existing Glaucoma = MUCH Higher Risk
Patients with pre-existing primary open-angle glaucoma (H40.1113 etc.) who receive corticosteroids have a significantly greater IOP response than the general population. [web:215] When a POAG patient receives intravitreal steroid for DME or wet AMD and subsequently develops elevated IOP with documented progression, the IOP response may represent worsening of pre-existing POAG (progression of existing H40.11xx code) OR conversion to drug-induced glaucoma (H40.61X1). The physician must document the etiology clearly — “IOP elevation due to intravitreal steroid” → H40.61X1; “POAG progression in setting of steroid” → H40.1xxx with progression staging.
Routes of Steroid Administration — All Can Cause SIG
| Route | IOP Elevation Risk | Clinical Notes |
|---|---|---|
| Intravitreal (triamcinolone, dexamethasone implant, fluocinolone) | ⬆⬆⬆ HIGHEST | Directly in vitreous — immediate local effect on TM; IOP check mandatory at every visit post-injection |
| Topical ophthalmic (prednisolone, dexamethasone, fluorometholone) | ⬆⬆ HIGH | Classic steroid responder trigger; onset 3-6 weeks; most commonly coded with H40.61X1 |
| Periocular / subconjunctival | ⬆⬆ HIGH | Similar to topical; long-acting depot preparations especially risky |
| Systemic oral (prednisone, methylprednisolone) | ⬆ MODERATE | Risk proportional to dose; chronic users (e.g., autoimmune disease) need annual IOP screening |
| Inhaled / intranasal | ⬆ LOW-MODERATE | Often overlooked — document and code when IOP link is established |
| Dermatological (periorbital) | ⬆ LOW | Systemic absorption through thin periorbital skin — rare but documented |
💊 Mandatory T-Code Assignment — Adverse Effect Coding
This is the most compliance-critical aspect of H40.61X1. The drug causing the glaucoma must be identified by T-code.
Adverse Effect vs. Poisoning — Critical Distinction
Steroid-Induced Glaucoma = Adverse Effect (T38.0X5x) — NOT Poisoning
An adverse effect occurs when a drug is taken correctly as prescribed and produces an unintended harmful consequence. Steroid-induced glaucoma in a patient taking prescribed corticosteroids for a legitimate indication (e.g., uveitis, post-surgical inflammation, rheumatoid arthritis) is an adverse effect — not a poisoning, not an underdosing.
The 5th or 6th character “5” in T-codes designates adverse effect:
- T38.0X5A = Adverse effect of glucocorticoids, initial encounter ✅
- T38.0X1A = Poisoning (accidental/unintentional) — NOT this scenario
- T38.0X6A = Underdosing — NOT this scenario
T-Code Quick Reference — Common Drugs at H40.61X1
| Drug Class | Specific Drug Examples | T-Code (Adverse Effect) | 7th Char |
|---|---|---|---|
| Glucocorticoids (most common) | Prednisone, prednisolone, dexamethasone, triamcinolone, fluocinolone, budesonide, fluticasone | T38.0X5A/D/S | A=initial, D=subsequent, S=sequela |
| Mineralocorticoids | Fludrocortisone | T50.0X5A/D/S | A/D/S |
| Antidepressants (anticholinergic → angle closure risk) | Amitriptyline, imipramine | T43.015A/D/S | A/D/S |
| Sympathomimetics | Ephedrine, pseudoephedrine | T44.991A/D/S | A/D/S |
The 7th Character of the T-Code — A, D, or S
The 7th character of the T-code must reflect the encounter phase for the adverse effect:
- A — Initial encounter: First time addressing the drug-induced glaucoma; new diagnosis visit; starting treatment
- D — Subsequent encounter: Follow-up visits for the same drug-induced glaucoma — the majority of ongoing monitoring visits
- S — Sequela: Long-term residual effects after the acute adverse effect is resolved
Most outpatient glaucoma monitoring visits for known steroid-induced glaucoma = T38.0X5D (subsequent encounter). Use A only at the initial presentation/diagnosis visit.
Full Code Pair — Standard H40.61X1 Encounter
Diagnosis Code 1 (Primary): H40.61X1 — Glaucoma secondary to drugs, right eye, mild
Diagnosis Code 2 (Required): T38.0X5D — Adverse effect of glucocorticoids, subsequent encounter
🔗 Related ICD-10-CM Codes
H40.61X Family — Right Eye, Secondary to Drugs
| Code | Description |
|---|---|
| H40.61X0 | Right eye, stage unspecified ⚠️ — query stage |
| H40.61X1 | Right eye, mild stage ← This Code |
| H40.61X2 | Right eye, moderate stage |
| H40.61X3 | Right eye, severe stage |
| H40.61X4 | Right eye, indeterminate stage |
Cross-Laterality — Same Stage
| Code | Description |
|---|---|
| H40.62X1 | Glaucoma secondary to drugs, left eye, mild stage |
| H40.63X1 | Glaucoma secondary to drugs, bilateral, mild stage |
| H40.60X1 | Glaucoma secondary to drugs, unspecified eye, mild stage ⚠️ |
Primary vs. Secondary — Right Eye, Mild Stage
| Code | Description | Key Distinction |
|---|---|---|
| H40.1111 | Primary open-angle glaucoma, right eye, mild | Idiopathic — no drug cause |
| H40.61X1 | Drug-induced glaucoma, right eye, mild ← This Code | Drug is identified cause — T-code required |
| H40.3110 | Glaucoma secondary to eye trauma, right, stage unspec. | Trauma cause — different T/S-code |
| H40.4110 | Glaucoma secondary to eye inflammation, right, stage unspec. | Uveitic glaucoma |
| H40.5110 | Glaucoma secondary to other eye disorders, right, stage unspec. | Pseudoexfoliation, pigment dispersion |
Commonly Co-Coded with H40.61X1
| Code | Description | Relationship |
|---|---|---|
| T38.0X5A / T38.0X5D | Adverse effect, glucocorticoids, initial/subsequent | MANDATORY — always paired |
| H26.11 | Anterior subcapsular polar age-related cataract | Steroid also causes posterior subcapsular cataract — dual complication |
| H26.13 | Posterior subcapsular polar cataract | Steroid-induced PSC — classic dual complication of chronic steroid use with SIG |
| H40.1111 | Primary OAG, right eye, mild | Pre-existing POAG — if concurrent and separately documented |
| Z79.52 | Long-term current use of systemic steroids | Documents chronic steroid exposure — supports medical necessity for IOP monitoring |
| Z79.899 | Other long-term drug therapy | If non-systemic steroid route not covered by Z79.52 |
| M06.9 | Rheumatoid arthritis | Common underlying condition requiring chronic steroids |
| M32.9 | SLE | Common underlying condition requiring chronic steroids |
| J45.x | Asthma | Inhaled steroids → less common SIG route but document when linked |
🛠️ CPT Codes — H40.61X1 Encounter Templates
Template A: Initial SIG Diagnosis Visit (Outpatient)
| Type | Code | Description | Notes |
|---|---|---|---|
| Exam | 92004 | Comprehensive ophthalmic exam, new patient | Full glaucoma evaluation |
| Visual field | 92083 | Visual field, extended (Humphrey 24-2 SITA Standard) | Stage determination — establishes MD value |
| OCT | 92133 | OCT anterior segment / optic nerve | RNFL analysis — structural staging |
| IOP | Bundled into exam | Goldmann applanation or non-contact | Baseline IOP documentation |
| Gonioscopy | 92020 | Gonioscopy | Confirm open angle — distinguish SIG from steroid-induced ACG |
| Modifier | -RT | Right eye | Append to unilateral procedure codes |
| Diagnosis | H40.61X1 | Primary | Drug-induced glaucoma, right eye, mild |
| Diagnosis | T38.0X5A | Additional — MANDATORY | Adverse effect glucocorticoids, initial encounter |
Template B: Established SIG Monitoring Visit (Outpatient)
| Type | Code | Description |
|---|---|---|
| Exam | 92014 | Comprehensive exam, established patient |
| Visual field | 92083 | HVF 24-2 SITA — progression monitoring |
| OCT | 92133 | RNFL OCT — structural progression monitoring |
| Diagnosis 1 | H40.61X1 | Primary |
| Diagnosis 2 | T38.0X5D | Required — subsequent encounter |
How Often to Monitor Mild Stage SIG
At mild stage (H40.61X1), typical monitoring includes:
- IOP check: Every 1-3 months while steroid is ongoing; every 3-6 months when steroid discontinued and IOP stable
- Humphrey visual field (92083): Every 6 months × 2 years to establish baseline progression rate; then annually if stable
- OCT optic nerve / RNFL (92133): Every 6-12 months
- If steroid is DISCONTINUED and IOP normalizes → consider whether H40.61X1 remains appropriate or transitions to glaucoma suspect (H40.0x)
Template C: Intravitreal Steroid + SIG Management (Ophthalmology — Retina + Glaucoma Overlap)
Crystal — This Is the AMD/Retina-Glaucoma Crossover Code
This scenario is extremely relevant to your AMD coding work! Patients receiving intravitreal triamcinolone (IVTA) or dexamethasone implant (Ozurdex) for diabetic macular edema or wet AMD may develop steroid-induced IOP elevation progressing to H40.61X1. When this occurs:
| Claim Line | Code | Description |
|---|---|---|
| Dx 1 | H40.61X1 | Glaucoma secondary to drugs, right eye, mild — SIG from intravitreal steroid |
| Dx 2 | T38.0X5D | Adverse effect of glucocorticoids, subsequent encounter — MANDATORY |
| Dx 3 | H35.3221 | Wet AMD, right eye, active CNV — underlying reason for steroid |
| Procedure | 67028-RT | Intravitreal injection (if anti-VEGF switch being made to avoid further SIG) |
Switching from Steroid to Anti-VEGF Due to SIG
When a patient has SIG (H40.61X1) from intravitreal steroid and the retina specialist switches to anti-VEGF therapy to avoid further IOP elevation, document the reason explicitly: “switching from steroid to bevacizumab/ranibizumab/aflibercept due to steroid-induced IOP elevation.” This supports medical necessity for the anti-VEGF selection and provides a complete clinical picture. Both the glaucoma code AND the retinal disease code should appear on the claim.
💊 Coding Scenarios
Scenario 1 — Classic Steroid-Induced Glaucoma, Topical Drops, Right Eye (Outpatient)
Clinical Vignette: A 58-year-old female was started on prednisolone acetate 1% QID, right eye only, 6 weeks ago after right eye trabeculectomy for primary open-angle glaucoma. She returns for follow-up. IOP OD: 32 mmHg (was 14 mmHg pre-drop). HVF 24-2: new small paracentral scotoma, MD -4.2 dB (was normal). OCT RNFL: early superior thinning OD. Impression: Steroid-induced IOP elevation with early glaucomatous damage, right eye — mild stage. Prednisolone tapered and switched to loteprednol. Starting brimonidine 0.2% OD.
ICD-10-CM:
- H40.61X1 — Glaucoma secondary to drugs, right eye, mild stage (new drug-induced glaucoma — MD -4.2 dB = mild)
- T38.0X5A — Adverse effect of glucocorticoids, initial encounter (prednisolone acetate — adverse effect; initial encounter for this complication)
- Z79.899 — Long-term use of other medication (documents ongoing glaucoma drop therapy)
CPT:
- 92014 — Comprehensive exam, established
- 92083 — Extended visual field (24-2)
- 92133 — OCT optic nerve/RNFL, right eye
- Append RT modifier to unilateral procedure codes
T38.0X5A vs. T38.0X5D — Initial vs. Subsequent
This is the first encounter specifically addressing the steroid-induced glaucoma as a new complication → T38.0X5A (initial). At the next follow-up visit for the same condition → T38.0X5D (subsequent).
Scenario 2 — Intravitreal Dexamethasone Implant (Ozurdex) → SIG (Retina Practice)
Clinical Vignette: A 71-year-old male with DME right eye received Ozurdex (dexamethasone 0.7mg intravitreal implant) 10 weeks ago. Follow-up IOP OD: 36 mmHg (baseline 15 mmHg). Optic nerve photos: new vertical C/D ratio increase 0.6 → 0.75. HVF 24-2: early superior arcuate defect, MD -3.8 dB. Impression: Drug-induced glaucoma from intravitreal dexamethasone implant, right eye, mild stage. Starting latanoprost OD.
ICD-10-CM:
- H40.61X1 — Glaucoma secondary to drugs, right eye, mild stage (Ozurdex-induced SIG)
- T38.0X5D — Adverse effect of glucocorticoids, subsequent encounter (dexamethasone implant — subsequent encounter; implant placed at prior visit)
- E11.3511 — Type 2 DM with diabetic macular edema, right eye (underlying reason for Ozurdex)
Ozurdex Is a Glucocorticoid — T38.0X5x Applies
Dexamethasone (Ozurdex) is a glucocorticoid → T38.0X5x is correct. The route of administration (intravitreal) does not change the T-code family — it is still an adverse effect of glucocorticoids (T38.0).
Scenario 3 — Stage Progression: Mild → Moderate (CDI Scenario)
Clinical Vignette: Patient with known H40.61X1 (drug-induced glaucoma, right eye, mild) returns 8 months later. Now on latanoprost + brimonidine. IOP 18 mmHg. HVF 24-2: MD now -7.8 dB (was -4.2 dB at mild stage). New visual field loss approaching horizontal meridian — not yet within 5° of fixation. OCT: moderate RNFL thinning. Impression: Drug-induced glaucoma, right eye — progressed to moderate stage.
ICD-10-CM — Stage Change:
- Retire H40.61X1 — no longer mild; progression documented
- H40.61X2 1 — Glaucoma secondary to drugs, right eye, moderate stage (MD -7.8 dB = moderate; >-6 dB threshold crossed)
- T38.0X5D — Adverse effect of glucocorticoids, subsequent encounter (drug cause still applies — even if steroid was discontinued, the drug caused the glaucoma)
T-Code Persists Even After Drug Discontinuation
The drug was the documented cause of the glaucoma. Even if the steroid was stopped months ago, the glaucoma code remains H40.61X1/2/3 (secondary to drugs) because the etiology is established, and the T38.0X5D code continues to document that the adverse effect of the drug was the precipitating cause. The condition does not “become” primary glaucoma just because the drug was stopped.
⚠️ Coding Pitfalls and Tips
| Pitfall or Tip | |
|---|---|
| ❌ | Never submit H40.61X1 without the T38.0X5x T-code — the “Use additional code” instruction at H40.6 is mandatory, not optional [web:207][web:211] |
| ❌ | Never code H40.61X1 for elevated IOP without documented glaucomatous damage — IOP elevation alone without optic nerve damage/visual field loss = ocular hypertension (H40.05x), not glaucoma |
| ❌ | Never confuse “adverse effect” T-code (5th/6th char = 5) with poisoning (1) or underdosing (6) — prescribed steroid causing SIG = adverse effect → T38.0X5x |
| ❌ | Never assign H40.61X1 and H40.11xx simultaneously for the same eye without clear physician documentation of two distinct glaucoma processes — query if ambiguous |
| ❌ | Never use the deleted H40.11X codes (pre-2016) when trying to code POAG — use H40.1111/1112/1113/1114 with laterality embedded |
| ✅ | The X in H40.61X1 is valid and required — it is a structural ICD-10-CM placeholder, not a gap. This code is current and billable. [web:199][web:209] |
| ✅ | T38.0X5A = initial encounter; T38.0X5D = subsequent encounter — use A at first diagnosis of SIG; D at all follow-up visits |
| ✅ | Stage the glaucoma from HVF mean deviation — mild = MD better than -6 dB; moderate = -6 to -12 dB; severe = worse than -12 dB |
| ✅ | Intravitreal steroid (Ozurdex, IVTA, Iluvien) → H40.61X1 — intravitreal route is still glucocorticoid adverse effect T38.0X5x |
| ✅ | Code Z79.52 (long-term systemic steroids) or Z79.899 alongside H40.61X1 to document the exposure history |
| ✅ | H26.13 (posterior subcapsular cataract) is the classic fellow traveler — steroids cause both SIG and PSC — code both when documented |
| ✅ | After steroid discontinuation, assess whether IOP normalizes — if it does and glaucoma reverses, consider transition to glaucoma suspect (H40.0x); if damage persists, H40.61X1-3 continues |
| ✅ | Right eye = RT modifier on all unilateral CPT procedure codes at this encounter |
📚 Sources
1. AAPC. “ICD-10-CM Code H40.61 — Glaucoma secondary to drugs, right eye.” Parent code — non-billable. Use additional code: T36-T50 (5th/6th char 5). Excludes 1: H44.51, Q15.0, P15.3. [web:207]
2. Unbound Medicine ICD-10-CM. “H40.61X1 — Glaucoma secondary to drugs, right eye [mild stage].” Full stage family H40.61X0-H40.61X4 confirmed. [web:208]
3. Coding Billing Solutions. “Glaucoma ICD-10 Codes.” H40.6 full family confirmed — H40.60X0-H40.63X4 — X placeholder structure confirmed as current and valid. [web:199][web:209]
4. AAPC. ICD-10-CM Code range H40-H42 — Glaucoma. H40.61X1 confirmed as active billable 7-character code under Glaucoma secondary to drugs, right eye, mild stage. [web:209]
5. Belgium Smart ICD-10 / WHO Tabular. H40.6 — “Use additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5).” [web:211]
6. AAPC. H40.62 — Glaucoma secondary to drugs, left eye. Use additional code instruction confirmed at H40.6 parent level for both laterality variants. [web:213]
7. StatPearls / NCBI. “Steroid-Induced Glaucoma.” Etiology (TM changes, GC receptor mechanism), steroid responder categories, routes of administration and IOP risk, monitoring guidelines. [web:215]
8. ICD-10-CM Official Guidelines for Coding and Reporting FY2025. Section I.C.7 — Diseases of the Eye and Adnexa; Adverse Effects, Poisoning, Underdosing and Toxic Effects (Section I.C.19).