Prior authorization — also called pre-authorization, pre-certification, or pre-approval — is a process insurers use to determine whether they'll cover a specific treatment, medication, or procedure before it's provided. A denial doesn't mean you can't get the treatment. It means your insurer, based on their initial review, has determined it doesn't meet their coverage criteria.

The critical thing to understand: prior authorization denials have multiple levels of appeal, and many are overturned — especially when a physician actively advocates for the patient.

What Prior Authorization Is and Why Insurers Require It

Insurance companies require prior authorization for treatments they consider expensive, potentially overused, or where there are often lower-cost alternatives. Common categories requiring prior authorization:

• Brand-name medications (especially when generics exist)
• Specialty medications (biologics, chemotherapy, some psychiatric drugs)
• Elective surgeries (joint replacement, certain cardiac procedures)
• Advanced imaging (MRI, CT scans in some cases)
• Out-of-network specialist referrals
• Inpatient mental health or substance use treatment
• Durable medical equipment (wheelchairs, CPAP machines)

Insurers argue that prior authorization reduces unnecessary procedures and directs patients to evidence-based, cost-effective care. Critics note that it creates administrative burden and treatment delays that harm patients — and that's often true, which is why the appeals process exists and has real teeth.

Why Prior Authorization Denials Happen

Understanding the reason for denial is essential — it determines your appeal strategy. Common denial reasons:

"Not Medically Necessary"

The most common denial reason. The insurer's reviewers determined the treatment isn't supported by clinical evidence for your specific condition, or that alternative treatments should be tried first ("step therapy" requirements). This requires your physician to document why the treatment is medically necessary for you specifically.

"Not in Network"

If the provider or facility isn't in your plan's network, authorization may be denied on that basis. Solution: either find an in-network equivalent, or request an exception (often available when there's no in-network equivalent nearby).

"Not a Covered Benefit"

Some services are explicitly excluded from your plan regardless of medical necessity. This is the hardest denial to appeal — you'd need to argue the exclusion doesn't apply to your situation, or seek a state external review on the grounds that the exclusion is unreasonable.

"Non-Formulary" or Wrong Tier

For medications, your plan has a formulary — a list of covered drugs organized into tiers (generic, preferred brand, non-preferred brand, specialty). If your doctor prescribed a non-formulary drug, it may be denied. Your doctor can request a formulary exception by documenting why a covered alternative won't work.

Incomplete Information

Sometimes a denial is simply because the prior auth request didn't include enough supporting documentation. These are often the easiest to resolve.

The Internal Appeal Process

All health insurance plans regulated under the ACA must provide at least one level of internal appeal. Here's how it works:

Standard Internal Appeal

Timeline:

• Non-urgent requests: Insurer must decide within 30 days
• Concurrent care (ongoing treatment): Must decide within 60 days
• Urgent/expedited requests: Must decide within 72 hours

What to do:

1. Request the specific reason for denial in writing (including the clinical criteria used)
2. Have your doctor write a letter of medical necessity — specific to your diagnosis, treatment history, and why alternatives won't work
3. Compile supporting documentation: clinical notes, test results, prior treatment records
4. Submit a formal written appeal to the address listed on the denial letter
5. Reference specific language from your insurance policy that supports coverage

What to Include in an Effective Appeal Letter

A strong appeal includes:

• Your member ID and claim/authorization number
• The specific service denied and the denial reason
• A detailed explanation of your medical history related to the condition
• Documentation that you've tried and failed alternatives (if step therapy was the basis)
• Peer-reviewed medical literature or clinical guidelines supporting the treatment
• A clear statement of how the denial meets the plan's definition of medical necessity

The more specific and evidence-based the appeal, the better your odds.

Peer-to-Peer Review: The Most Underused Tool

Many patients don't know about this option: peer-to-peer review allows your treating physician to speak directly with the insurance company's medical reviewer by phone, typically within 1–3 business days of the denial.

This is often the single most effective step for overturning a denial. The insurance reviewer who denied the claim may not be a specialist in your condition — a direct conversation between physicians allows your doctor to provide clinical nuance that doesn't fit into a form.

Ask your doctor's office to request a peer-to-peer review immediately after a denial. Many offices have staff who do this regularly.

External Independent Review

If your internal appeal is exhausted and you still believe the denial is wrong, most states provide the right to external independent review — an independent organization (not affiliated with your insurer) reviews the clinical basis for the denial.

Timeline:

• External review decision within 45 days (standard)
• Within 72 hours for urgent care

Under ACA rules, if the external reviewer overturns the denial, the insurer is legally required to cover the service. Approval rates at external review are significant — studies suggest 40–60% of appealed cases are overturned.

You generally have 60–180 days from the final internal appeal denial to request external review, depending on your state.

How to request: Contact your state insurance commissioner's office, or your employer plan's human resources department if it's a self-insured employer plan (which is regulated by the Department of Labor, not your state).

Success Rates at Each Stage

Published research on appeal outcomes shows:

• Internal appeal: Varies widely, but patients who file complete appeals with physician support win roughly 40–50% of cases
• Peer-to-peer review: Among the most effective interventions — success rates of 50–75% have been reported depending on the specialty
• External review: Roughly 40–60% of external reviews result in the denial being overturned

These numbers explain why it's always worth appealing. Insurers count on most patients giving up after the initial denial.

If You Need the Treatment Urgently

For medically urgent situations where waiting for the standard appeal timeline could harm you:

• Request an expedited internal appeal (must be decided in 72 hours)
• Simultaneously request an expedited external review
• Ask your doctor to document the urgency explicitly

In emergency situations, you can receive care without prior authorization — you cannot be denied emergency coverage for seeking immediate necessary care.

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