A Prior Authorization Denial Is Not the End of the Road
Your doctor prescribed a treatment. Your insurer said no — not because you don’t need it, but because a form came back marked “denied.” If you’re staring at a prior authorization denial right now, the most important thing to understand is this: a PA denial is the beginning of a negotiation, not the end of one. Roughly 30 percent of prior authorization requests are denied on first submission, but the majority of those that are appealed end up approved. The insurer is counting on you not to appeal. Most people don’t.
This guide explains what a prior authorization is, why insurers deny them, what step therapy is and how to get around it, and exactly how to appeal — step by step — so that your denial follows the same path as the majority that get reversed.
What Is a Prior Authorization, and Why Do Insurers Require Them?
A prior authorization (also called a PA, pre-authorization, or pre-certification) is a requirement that your insurer approve a medication, procedure, test, or piece of medical equipment before they’ll agree to pay for it. Your doctor submits clinical information, and the insurer decides whether the treatment meets their coverage criteria.
Insurers say prior authorization exists to control costs and ensure treatments are appropriate and evidence-based. In practice, it functions as a gatekeeping step — an extra hurdle that delays or blocks expensive treatments. The criteria are often opaque, the review is frequently done by someone who has never met you, and the default answer for anything costly is “not yet.”
None of that means the denial is correct. It means you have to make the case that the treatment your doctor already decided you need meets the insurer’s written rules. And usually, it does.
The Most Common Reasons a PA Gets Denied
Denials tend to fall into a handful of categories. Identifying which one you’re dealing with tells you exactly what your appeal needs to say.
- Step therapy required. The insurer wants you to try one or more cheaper treatments first before they’ll cover the one your doctor prescribed. This is the single most common reason for a PA denial. (More on how to beat it below.)
- “Not medically necessary.” The insurer claims the treatment isn’t needed based on the information they received. Often this simply means the submitted documentation didn’t spell out the clinical justification in the terms their criteria require.
- Formulary exclusion. The drug isn’t on the insurer’s covered list (formulary), or it’s in a tier that requires special approval. There is almost always a formulary exception process to request coverage anyway.
- Incomplete or missing documentation. A box wasn’t checked, a lab value wasn’t attached, a diagnosis code was missing. A surprising share of denials are purely administrative and can be fixed by resubmitting with the missing piece.
- Quantity or dosage limits. The insurer covers the drug but not at the amount or frequency prescribed. This too can be appealed with a justification from your doctor.
Your denial letter should state the reason. If it doesn’t — or if the reason is vague — you have the right to request the specific clinical criteria the insurer used to make the decision. Ask for it in writing.
Step Therapy: What It Is and How to Get Around It
Step therapy — sometimes called “fail first” — requires you to try and fail on the insurer’s preferred (usually cheaper) treatments before they’ll approve the one your doctor actually wants you on. If your prescriber skips straight to the more effective or more expensive option, the PA comes back denied with instructions to “step through” the alternatives first.
Step therapy can be genuinely harmful when a patient is forced to fail on a drug their physician already knows won’t work, or to abandon a treatment that’s currently working just because they switched plans. Fortunately, most states have passed step therapy override laws that require insurers to grant an exception when certain conditions are met. The exact rules vary by state, but the standard override grounds are:
- You’ve already tried the required drug (on this plan or a previous one) and it didn’t work or stopped working.
- The required drug is expected to be ineffective based on your clinical profile.
- The required drug is likely to cause harm or an adverse reaction.
- The required drug is contraindicated for you.
- You are stable on your current treatment and switching would be medically inadvisable.
If any of these apply, your doctor can request a step therapy exception citing your state’s override law. The insurer typically has to respond within a set timeframe (often 72 hours for standard requests and 24 hours for urgent ones). Naming the specific override criterion that applies to you — in writing, from your prescriber — is the fastest route through a step therapy wall.
How to Appeal a PA Denial, Step by Step
Every insured person in the U.S. has a legal right to appeal a coverage denial. There are two main stages: the internal appeal (handled by the insurer) and, if that fails, the external review (handled by an independent third party).
1. Read the denial letter and identify the reason and the deadline
The letter must tell you why the request was denied and how to appeal. Note the deadline carefully — for most plans you have 180 days from the denial to file an internal appeal. Mark it on your calendar. Missing the window is the most common way a winnable appeal is lost.
2. Request the clinical criteria the insurer used
You’re entitled to know the exact guidelines the reviewer applied. This tells you precisely what your appeal has to prove. If the denial says “not medically necessary,” the criteria document tells you what “medically necessary” means to this insurer — so you can meet it point by point.
3. Gather your documentation
This is where appeals are won or lost. Assemble:
- A letter of medical necessity from your prescribing doctor. This is the centerpiece. It should describe your diagnosis, why this specific treatment is appropriate, what alternatives have been tried or ruled out, and what happens clinically if the treatment is delayed or denied.
- Your prior treatment history — records of any drugs or therapies you’ve already tried, including which failed and why. This is essential for step therapy overrides.
- Clinical evidence — peer-reviewed studies, treatment guidelines from medical societies, and FDA approval information supporting the treatment for your condition. This matters most for “experimental/investigational” denials and rare-disease cases.
- Any lab results, imaging, or test values the criteria reference.
4. File the internal appeal
Submit a written appeal that directly addresses the denial reason, attaches your documentation, and cites the specific coverage criteria you meet (and any state override law, if step therapy is involved). Keep copies of everything and send it in a way you can track.
5. Escalate to external review if the internal appeal fails
If the insurer upholds the denial, you can request an independent external review, in which an outside medical reviewer with no stake in the outcome evaluates your case. The external reviewer’s decision is binding on the insurer. External review overturns a meaningful share of denials that insurers refused to reverse internally — it’s well worth pursuing.
Timelines and Deadlines: Urgent vs. Standard
Speed depends on urgency. If waiting would seriously jeopardize your health, you can request an expedited (urgent) appeal:
- Urgent/expedited appeals: insurers generally must decide within 72 hours. Urgent external reviews are often even faster.
- Standard pre-service appeals: typically decided within 30 days.
- Standard post-service appeals (care already received): typically within 60 days.
If your situation is time-sensitive, say so explicitly and ask your doctor to document the urgency. You do not have to exhaust the standard internal appeal before requesting an expedited external review in genuinely urgent cases.
The Odds Are Better Than You Think
Insurers deny roughly 30 percent of prior authorization requests up front, but a large majority of appealed denials are ultimately overturned. The gap between those two numbers is the space where insurers rely on patients giving up. Appeals take effort — a few phone calls, a letter, some documentation gathering — but the payoff is often the difference between paying nothing and paying out of pocket for a treatment your doctor already decided you need.
The most powerful move you can make is simply to file. A denial that’s never appealed is a denial the insurer keeps. A denial that’s appealed with the right documentation usually isn’t.
How AskBenji Helps
Reading the criteria, matching your situation to the right override law, and writing a letter of medical necessity that hits every point the insurer requires is a lot to do while you’re also dealing with an illness. AskBenji analyzes your denial letter and drafts the appeal for you — free at askbenji.co/denial. Upload the denial and within minutes you’ll get a plain-language breakdown of why it was denied, the specific regulations and clinical evidence that support your case, and a ready-to-send appeal letter written in your voice.
Your documents are processed ephemerally and deleted after 24 hours. No PHI is stored, no account is required, and the service is free.
For more on decoding what your insurer sent you, read How to Read Your Insurance Denial Letter (And What to Do Next). And if your denial involves out-of-network or surprise charges, see The No Surprises Act: What It Means for Your Medical Bills.