Does R79.9 require prior authorization?

No, R79.9 does not require prior authorization (high confidence). Code is covered without prior authorization.

`R79.9` — Abnormal finding of blood chemistry, unspecified

ICD-10-CM

No Prior Auth Required

Code is covered without prior authorization (high confidence)

This article provides billing, coding and guideline information that complements Local Coverage Determination (LCD) L33431 for HbA1c; refer to LCD L33431 for clinical coverage criteria and specific documentation requirements.
The article provides billing/coding guidance that complements LCD L39400; use the documentation, prior authorization, and claim submission requirements specified in LCD L39400 and the local contractor's instructions.
Document two consecutive HbA1c results meeting treatment goals to support classification of 'stable glycemic control.'
Provide medical records demonstrating medical necessity for any additional HbA1c tests beyond standard or NCD/local frequency limits when requesting reimbursement on appeal.

No specific clinical indications are listed in this article; follow the Local Coverage Determination (LCD) L39400 for indications for magnesium testing or services.
Perform HbA1c testing at least twice per year in patients who are meeting individualized treatment goals and have stable glycemic control, defined as two consecutive HbA1c results meeting treatment goals.
Perform HbA1c testing for beneficiaries with unstable or uncontrolled glycemia at intervals up to once every 3 months as allowed by the Lab NCD 190.21.
Beneficiaries eligible for the Medicare home health benefit often have multiple coexisting illnesses and may have higher individualized HbA1c targets that justify more frequent testing.
Serum magnesium testing is covered when hypomagnesemia is suspected due to gastrointestinal or renal losses or when patients present with symptoms of low magnesium (weakness, muscle cramps, confusion, irregular heartbeat, or seizures).
Serum magnesium testing is covered for patients with conditions known to cause hypomagnesemia (examples include cardiac arrhythmias, proton pump inhibitor use, chronic alcohol use, uncontrolled diabetes mellitus, hypercalcemia, post–organ transplant status, inherited renal magnesium wasting, malabsorption syndromes, aminoglycoside or amphotericin B nephrotoxicity, cisplatin, pentamidine, calcineurin inhibitor therapy, digoxin use, prolonged IV or nasogastric therapy, parenteral alimentation with [...]

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ANTHEM-CG-LAB-21 — CG-LAB-21 Serum Iron Testing

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A56686 — Billing and Coding: HbA1c

Ask Verity about documentation requirements, denial risks, or coverage in your state.