CO-151 — Frequency / quantity not supported
Claim-adjustment reason code 151 · typically reported as CO-151
What it means
The payer says the number of units or frequency billed exceeds what the documentation or policy supports — the MUE/utilization denial.
Why DME claims hit it
- Units above the Medically Unlikely Edit (MUE) for the HCPCS
- Resupply ahead of the allowed replacement cadence (e.g., CPAP masks/tubing)
- Quantity per delivery exceeding policy norms without documented need
How to fix it
- Check the MUE value and its adjudication type before billing
- For legitimate high utilization, document the clinical reason and bill per the payer’s units guidance
- Align resupply schedules to policy cadences and patient-confirmed need
Appeal posture
Appealable with records proving necessity of the quantity; MUE "per-line" denials can sometimes be corrected via proper line-splitting per payer guidance.
Related denial codes
CO-119 — Benefit maximum reachedCO-273 — Coverage guidelines exceededCO-18 — Exact duplicate claim or serviceCO-50 — Not deemed medically necessary
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