Challenge Ingestion Food Testing — NCD 187 | CMS Coverage Update

TL;DR: The Centers for Medicare & Medicaid Services modified NCD 187 governing challenge ingestion food testing, effective March 7, 2026. Here's what billing teams need to know.

CMS challenge ingestion food testing coverage policy under NCD 187 in the Medicare system draws a clear line between covered and non-covered uses. The policy confirms this procedure is covered on an outpatient basis when it's reasonable and necessary for the individual patient — specifically for diagnosing food allergies. It is not covered when used to diagnose rheumatoid arthritis, depression, or respiratory disorders. No specific CPT or HCPCS codes are listed in this policy document, which creates its own set of billing challenges (more on that below).

---

Quick-Reference Table

Field	Detail Copy
Payer	CMS (Centers for Medicare & Medicaid Services)
Policy	Challenge Ingestion Food Testing
Policy Code	NCD 187
Change Type	Modified
Effective Date	2026-03-07
Impact Level	Medium
Specialties Affected	Allergy & Immunology, Internal Medicine, Gastroenterology, Rheumatology
Key Action	Confirm diagnosis code supports food allergy — not rheumatoid arthritis, depression, or respiratory disorders — before submitting any challenge ingestion food testing claim

---

CMS Challenge Ingestion Food Testing Coverage Criteria and Medical Necessity Requirements 2026

NCD 187 is the National Coverage Determination governing Medicare coverage of challenge ingestion food testing. The policy is short, but it carries a specific medical necessity standard your billing team needs to get right.

Coverage is allowed on an outpatient basis when the procedure is "reasonable and necessary" for the individual patient. That language comes directly from section 1862(a)(1) of the Social Security Act — the same statutory hook CMS uses across hundreds of NCDs to tie coverage to clinical appropriateness.

The covered use case is narrow: diagnosing food allergies. If the ordering provider documents food allergy as the clinical question, and the setting is outpatient, you have a defensible claim under this coverage policy.

The medical necessity requirement here is patient-specific. That matters because it means cookie-cutter documentation won't hold up. You need the chart to reflect why this particular patient needs challenge testing — not just a diagnosis code.

There's no prior authorization requirement listed in this NCD. That said, your Medicare Administrative Contractor (MAC) may have a local coverage determination (LCD) that adds prior auth or documentation requirements on top of this NCD. Check your MAC's policies before you assume prior authorization isn't needed.

Challenge ingestion food testing billing under this NCD is straightforward in principle: outpatient setting, food allergy diagnosis, individualized medical necessity. The execution — especially the documentation — is where claims fall apart.

---

CMS Challenge Ingestion Food Testing Exclusions and Non-Covered Indications

This is where NCD 187 gets specific, and where your claim denial risk is highest.

CMS states explicitly that challenge ingestion food testing has not been proven effective for three conditions:

#	Excluded Procedure Copy
1	Rheumatoid arthritis
2	Depression
3	Respiratory disorders

Claims submitted with those diagnoses as the basis for testing will be denied. CMS calls it out directly: this use is "not reasonable and necessary" under section 1862(a)(1). No program payment will be made.

The real issue here is mixed-diagnosis cases. A patient with both rheumatoid arthritis and suspected food allergies is a claim risk. If the documentation doesn't clearly tie the test to food allergy diagnosis — and not to the RA workup — you're exposed.

Rheumatology practices should pay close attention. This isn't a theoretical risk. Some providers have used food challenge testing as part of an investigation into inflammatory or autoimmune conditions. CMS doesn't cover that. The policy is direct about it.

The same logic applies to behavioral health billing. Depression as a primary or contributing diagnosis for this test is a non-starter under Medicare. If you see this combination in your claims queue, flag it before submission.

Respiratory disorders are the third excluded category. Allergists who test patients with asthma or other respiratory conditions should document carefully. Food allergy and respiratory disorders can coexist in the same patient — asthma triggered by food allergy being the obvious example. Your documentation needs to show the test is for food allergy diagnosis, full stop.

---

Coverage Indications at a Glance

---

CMS Challenge Ingestion Food Testing Billing Guidelines and Action Items 2026

The effective date of March 7, 2026 means this modified policy is already in effect. If your team hasn't reviewed your charge capture and documentation workflows against this NCD, do it now.

Copy Action Items

---

CPT, HCPCS, and ICD-10 Codes for Challenge Ingestion Food Testing Under NCD 187

NCD 187 does not list specific CPT, HCPCS Level II, or ICD-10-CM codes. This is worth flagging directly — the absence of codes in this policy document creates real billing ambiguity.

No Codes Specified in NCD 187

Code	Type	Notes Copy
Not listed	CPT/HCPCS	NCD 187 does not include specific procedure codes. Refer to your MAC's claims processing instructions for applicable codes.

This is not unusual for older NCDs — many predate the current code sets. But it puts the burden on your billing team to identify the right code through MAC-level guidance.

The NCD cross-references claims processing instructions. Pull those instructions from your MAC's website or portal. If your MAC has an LCD for challenge ingestion food testing, that document will likely specify the relevant codes more precisely.

If you're billing for a physician-supervised oral food challenge in an outpatient clinical setting, your coding team may look at evaluation and management codes, allergen immunotherapy codes, or unlisted procedure codes depending on payer guidance. Don't guess. Get written MAC guidance or a compliance opinion before you establish a standard code for this service.

The lack of explicit codes in this coverage policy is the most operationally challenging aspect of NCD 187. Your revenue cycle team needs a clear internal policy on how to code this before claims go out. Document that decision and the rationale. You want a paper trail if a claim is audited.

---