N668 Remark Code: Prescription Incomplete or Invalid

What N668 means

This time the payer did get a prescription. The problem is its content. A valid prescription generally identifies the patient, the item or service, the quantity or duration, the date, and the prescriber, with a proper signature. Many payers add their own elements, such as a diagnosis, length of need, or a detailed item description. When one of these is missing or doesn’t hold up, the payer returns N668.

Typical defects

• Missing or unacceptable signature, such as an unsigned form or a stamped signature.
• No date, or a date after delivery, when the payer requires the order first.
• Item mismatch: the prescription names something different from what was billed, or is too vague to identify it.
• Quantity or frequency missing, especially for supplies and drugs.
• Expired prescription, beyond the period the payer or state allows.
• Prescriber not authorized to order that item under state scope of practice or the payer’s rules.

How to fix it

1. Compare the prescription to the payer’s documentation checklist for the item and note each gap.
2. Ask the prescriber for a corrected or new prescription, or a signature attestation if the payer accepts one.
3. Resubmit the corrected document through the payer’s attachment process, or send a corrected claim with resubmission code 7 in box 22 if the claim details also changed.
4. Match the claim to the prescription, including item description, quantity in box 24G, and the ordering provider in box 17 and 17b where the payer requires it.

How to prevent it

Use a prescription intake checklist based on each major payer’s requirements, and check every prescription before the item is delivered. Returning a flawed prescription to the prescriber before the service is much easier than fixing it after a denial.