OIG Report: Medicare Payments for Continuous Glucose Monitors

A recent OIG report found that Medicare may be overpaying suppliers for Continuous Glucose Monitors (CGMs) and supplies relative to other payers.

The report highlighted the following:

  • Medicare Part B payments have increased dramatically from $109 million in 2018 to $1.3 billion in 2023
  • Medicare payments for CGM supplies exceeded supplier acquisition costs by $359 million and total estimated costs by $61 million in 2022-2023
  • From July 2022 through June 2023
    • 93% of the payments were for monthly supplies, while only 7% were for CGM devices
    • 98% of CGMs and supplies were provided via mail order
  • Suppliers received $7 million in potential overpayments based on improper coding of CGMs and supplies (e.g. via inappropriate use of KF modifier)

As a result of the findings, OIG has recommended that CMS reduce payments for CGMs and supplies and address improper use of billing codes to reduce overpayments.

CMS has included Class 2 CGMs and supplies in the next round of the DMEPOS Competitive Bidding Program as per Final Rule (CMS-1828-F) published December 2, 2025 which would both reduce prices and limit the number of suppliers eligible to bill for CGMs and related supplies. This process is expected to begin in 2026 and be completed no later than January 1, 2028. Previous rounds of competitive bidding yielded an average savings of 35% relative to the fee schedule prices.

The DMEPOS MAC for Jurisdictions B and C have posted the Medical Review Quarterly Reports for Targeted, Probe, and Educate (TPE) audits covering July to September 2025 and found that Glucose Monitors & Supplies have an 18.52% error rate overall and provides the top 10 denial reasons.

PAAS Tips:

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Did you know there is much more to your audit assistance membership than just help with audits? The PAAS Member Portal contains a wealth of information and resources to assist you with audits and member service questions. Below is a list of 6 pages found on the Audit Assistance section of the PAAS Member Portal to assist you and your pharmacy staff to be proactive when it comes to audits.

  • Access Services
    • Audit Documentation Submission Guidance
    • An online form to submit safe filling and billing questions
    • Your PAAS Membership Manual
  • Newsline
    • Monthly newsletter articles, written by our expert PAAS analyst team, provide safe filling and billing tips and relays relevant/current PBM trends to be help prevent audits
    • Search the Newsline Archive to get PAAS tips at the click of a button
    • Special Edition Newslines including: Top 10 articles of the prior year, DMEPOS Article Series and a Self-Audit Article Series
    • Ability to print monthly issues or individual articles
  • Proactive Tips
    • Audit flags – list of various claim attributes the PBMs use to select claims for audit
    • Billing insulin vials – flowchart to assist whether you should bill Medicare Part B vs Part D
    • DAW Codes Explained – use to understand when to effectively use DAW codes, their definitions and why claims may be flagged for audit if a DAW code is used incorrectly
    • Basic DMEPOS documentation guidance
    • Onsite Credentialing Checklist and expanded definitions of policies and procedures
    • Proof of refill request and affirmative response form for DMEPOS items
    • Steps on how to prepare for an onsite audit
    • And more!
  • Days’ Supply Charts
    • Utilize the days’ supply charts for inhalers, insulins, nasal sprays, eye drops and topicals to aid you in calculating the correct days’ supply
    • Guidance on overbilled quantities and incorrect days’ supply account for a sizable portion of audit chargebacks
    • Additional miscellaneous charts, which include: Dispense in Original Container and Return to Stock
  • Forms
    • Signature Logbook for print
    • Signature Trifold Mailer
    • Fax and Email Coversheet
    • Patient Attestation for over-the-counter COVID-19 test kits
  • On-Demand Webinars
    • Short webinars on hot topics in the PBM industry. Here are a few examples:
      • USP 800 Compliance
      • Cultural Competency Training
      • Dispensing Prescriptions Off-Label
      • Biologic Medications and Interchangeability
      • Continuous Glucose Monitor Requirements for Medicare Part B

PAAS Tips:

  • MORE AUDITS, MORE INSIGHT – PAAS National® is the industry-leading defender of community pharmacy dealings with Prescription Benefit Programs, including Caremark, Express Scripts, Humana, Medicaid, OptumRx, Prime Therapeutics., and more. PAAS assists on all third-party audits, including: desktop audits, onsite audits, invoice audits, OIG/Medicaid audits, Medicare B audits. The PAAS team is dedicated to helping you! We have five pharmacists and a complement of technician analysts with over 50 years of dedicated audit assistance experience. PAAS continuously updates their database with every audit received — in fact, we even keep a scorecard on individual auditors.
  • Get answers to your questions on days’ supply calculations, drug substitutions, billing practices, required documentation, prior authorization requirements, record retention, and internal audit procedures – just to name a few. As a trusted partner, we will provide tailored guidance to help you proactively prevent audits. Remember, the prescription claims you submit today are the audits of the future.
  • Keep your employees engaged and help lower audit risk by adding all employees to the portal and giving them permission to access these tools, resources and eNewsline. For more information review September 2019 Newsline article, What Are You Waiting For? Make Sure ALL of Your Employees are Added to the PAAS Portal!
  • Contact PAAS at (608) 873-1342, if you would like a tour of your PAAS Member Portal, so you can reap all the benefits of your PAAS Audit Assistance. We appreciate you being a member.
Eric Hartkopf, PharmD
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