| Internal Appeal Deadline | Up to 180 days from denial |
| Expedited Appeal Decision | Within 72 hours |
| Standard Appeal Decision | 30β60 days |
| External Appeal Eligibility | After exhausting internal appeals |
| Key Document Required | Letter of Medical Necessity |
| Governing Law | ACA & ERISA |
Key Takeaways
- Most CGM denials are overturned on appeal when properly documented
- You have the legal right to appeal any insurance denial under the ACA
- A Letter of Medical Necessity from your doctor is essential
- Deadlines matter β file within 30β180 days depending on your plan
- External appeals are available if internal appeals fail
Why CGMs Get Denied
Continuous Glucose Monitors (CGMs) are frequently denied by insurers citing lack of medical necessity, formulary restrictions, or outdated coverage policies. Common denial reasons include: not meeting insulin-dependence criteria, using a non-preferred brand, or missing prior authorization. Understanding the exact denial reason from your Explanation of Benefits (EOB) is the critical first step.
Step-by-Step Appeal Process
Step 1: Request the Denial in Writing
Call your insurer and request a written denial letter with the specific reason code. You are legally entitled to this under ERISA and ACA regulations.
Step 2: Obtain a Letter of Medical Necessity
Ask your endocrinologist or primary care physician to write a detailed Letter of Medical Necessity (LMN). The letter should include your diagnosis (ICD-10 codes E11.x for Type 2, E10.x for Type 1), HbA1c history, hypoglycemia episodes, and why a CGM is clinically required over fingerstick testing.
Step 3: Gather Supporting Evidence
- Peer-reviewed studies showing CGM efficacy
- ADA Standards of Care recommending CGM use
- Your personal glucose logs and hypoglycemia records
- Any prior CGM data showing clinical benefit
Step 4: Write Your Appeal Letter
Address the specific denial reason directly. Use clinical language, cite ADA guidelines, and request an expedited review if your condition is urgent. Include your policy number, claim number, and all supporting documents.
Step 5: File Within Deadlines
Most plans allow 180 days from denial to file an internal appeal. Expedited appeals (for urgent medical need) must be decided within 72 hours by law.
Internal vs. External Appeals
| Appeal Type | Who Reviews | Timeline |
|---|---|---|
| Internal Appeal | Your insurance company | 30β60 days |
| External Appeal | Independent review organization | 45β60 days |
| Expedited Appeal | Insurer or IRO | 72 hours |
Key Arguments That Win Appeals
- Hypoglycemia unawareness: CGMs are life-saving for patients who cannot detect low blood sugar
- Clinical guidelines: ADA 2024 Standards recommend CGM for all insulin-using patients
- Cost-effectiveness: CGMs reduce ER visits and long-term complications
- Prior authorization errors: Many denials result from administrative mistakes
FSA/HSA as a Backup Option
If your appeal is unsuccessful, CGM devices and sensors are FSA and HSA eligible expenses. Using tax-advantaged funds reduces your out-of-pocket cost by 20β30% depending on your tax bracket. MDS Diabetes offers a wide selection of FSA/HSA-eligible CGM supplies including sensors, transmitters, and accessories at competitive prices.
When to Escalate
If both internal and external appeals fail, file a complaint with your state's Department of Insurance. For Medicare denials, contact your State Health Insurance Assistance Program (SHIP). Patient advocacy organizations like Beyond Type 1 also offer free appeals assistance.