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A4774 Ammonia test strips

A Codes

Also known as: ammonia strips, ammonia test, NH3 test strips

Disposable test strips that detect and quantify ammonia levels in blood samples. Used to assess hepatic synthetic function and encephalopathy risk.

In Plain Language

test strips for liver function; ammonia level test

Clinical Context

Used in patients with liver disease to monitor ammonia levels and assess risk for hepatic encephalopathy. Helps guide treatment decisions.

RVU Information

CPT A4774 does not have a physician work RVU assigned by CMS. This is typical for supply, drug, and equipment codes — reimbursement is based on Average Sales Price (ASP), fee schedules, or payer contracts rather than the RVU system.

Billing & Documentation

HCPCS A-codes cover medical supplies, equipment, and transport services. Documentation must establish medical necessity and include a physician order. For durable medical equipment (DME), a Certificate of Medical Necessity (CMN) or detailed written order may be required.

Specialties

HepatologyGastroenterologyLaboratory

Frequently Asked Questions

What is CPT code A4774?

CPT A4774 (Ammonia test strips) is a A Codes code. Disposable test strips that detect and quantify ammonia levels in blood samples. Used to assess hepatic synthetic function and encephalopathy risk.

Does Medicare cover A4774?

Medicare coverage for A4774 depends on medical necessity and applicable Local Coverage Determinations (LCDs). Used in patients with liver disease to monitor ammonia levels and assess risk for hepatic encephalopathy. Helps guide treatment decisions. A physician order is typically required.

When is CPT A4774 used?

Used in patients with liver disease to monitor ammonia levels and assess risk for hepatic encephalopathy. Helps guide treatment decisions.

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CPT® is a registered trademark of the American Medical Association. Data sourced from CMS Physician Fee Schedule RVU26A. Descriptions, synonyms, and clinical context are original content by RVU Edge.