Pre-authorization, sometimes called prior authorization or PA, is a requirement by your health insurer that your doctor get approval before delivering a specific treatment, test, procedure, or medication. The insurer reviews the request against clinical criteria and decides whether the service is medically necessary and covered under your plan before you receive it. The system was introduced in the 1960s as a cost-containment tool for Medicaid and expanded broadly across commercial managed care in the 1980s and 1990s. What started as a relatively narrow gatekeeping mechanism has grown into a sprawling process touching everything from MRI scans to cancer drugs, and its real-world effects on patients, doctors, and costs are far more complicated than the original concept suggests.
The Step-by-Step Process
The sequence begins when your doctor determines you need a particular service, whether that is a medication, imaging study, surgical procedure, or specialist referral. Before ordering or prescribing it, your doctor’s office checks whether your insurance plan requires pre-authorization for that specific service. If it does, the office submits a request to your insurer, typically including your diagnosis, relevant medical records, lab results, and a clinical justification explaining why the service is needed.
The insurer’s utilization management team then reviews the submission against a set of clinical criteria. These criteria are often based on national clinical guidelines and are meant to ensure that the requested service is evidence-based and appropriate for your condition.1PubMed Central. Prior Authorization and Utilization Management Concepts in Managed Care Pharmacy In many cases, a nurse or clinical reviewer handles the initial decision. If the request meets the insurer’s criteria, it gets approved, and your doctor proceeds with the care. If it does not, the request is denied, and your doctor is notified along with the reason for denial. The entire cycle can be resolved in a single business day or drag on for weeks, depending on the complexity of the request and the insurer’s processes.
What catches many people off guard is that approval is not guaranteed even when your doctor believes the treatment is clearly necessary. The insurer is making an independent judgment about medical necessity based on its own guidelines, and those guidelines do not always match your doctor’s clinical reasoning. This disconnect is the root of most frustrations with the system.
What Requires Pre-Authorization
There is no universal list. Each insurer decides which services require pre-authorization, and the requirements vary widely even among plans offered by the same company. A cross-sectional study of Medicare Advantage insurers found that the number of clinical services requiring PA ranged from about 950 to nearly 3,000 out of roughly 14,000 total services, depending on the insurer.2PubMed Central. Comparison of prior authorization across insurers: cross sectional evidence from Medicare Advantage About 40% of Medicare Part B spending and nearly half of service utilization would have required PA by at least one insurer, though only about 12% of spending required it from every insurer studied.2PubMed Central. Comparison of prior authorization across insurers: cross sectional evidence from Medicare Advantage Medications were hit especially hard: about 93% of Part B medication spending would have required PA by at least one Medicare Advantage insurer.
In practice, the categories most commonly subject to PA include specialty medications (biologics, cancer drugs, certain diabetes treatments), advanced imaging (MRI and CT scans), surgical procedures, durable medical equipment, and some specialist referrals. If you have employer-sponsored insurance, your plan documents or your insurer’s website will list which services require pre-authorization. Failing to get PA when it is required can mean your insurer refuses to pay for the service entirely, leaving you with the full bill.
The Time and Money It Costs Your Doctor’s Office
One of the less visible effects of pre-authorization is the enormous administrative machinery it requires on the provider side. A study in a dermatology department found that staff spent a median of 12 minutes per PA request, though some took far longer. The most time-consuming single case involved a biologic medication and consumed 148 minutes of staff time, costing about $80 in administrative expenses alone, which exceeded the Medicare reimbursement for the associated clinic visit.3JAMA Dermatology. Administrative Burden and Costs of Prior Authorizations in a Dermatology Department
In radiation oncology, the numbers are starker. Researchers estimated that each PA event consumed roughly 50 to 95 minutes of practice time and cost between $28 and $101, with peer-to-peer discussions pushing costs toward the higher end. A single academic radiation oncology department estimated its annual PA-related costs at nearly $492,000, with about 94% of that spending going toward treatments that were ultimately approved.4PubMed. Estimating the Practice-Level and National Cost Burden of Treatment-Related Prior Authorization for Academic Radiation Oncology Practices Nationally, the researchers estimated treatment-related PA costs in radiation oncology alone at over $40 million per year, with the vast majority spent processing requests that ended in approval. That is money spent proving that care already deemed necessary by a specialist was, in fact, necessary.
For neurologic medications, a scoping review found that the most frequently identified consequence for clinicians and administrators was time burden.5JAMA Neurology. Barriers and Consequences of Prior Authorization for Neurologic Medications: A Scoping Review These administrative hours are not free. They pull staff away from direct patient care and add overhead costs that ultimately get passed along through the healthcare system.
What Happens When Your Request Is Denied
A denial does not have to be the end of the road. You or your doctor can appeal the decision, and the data strongly suggest that appealing is worth the effort. Among Medicare Advantage plans, about 67% of denied PA requests that were appealed were ultimately overturned. In Medicaid managed care, the overturn rate was about 47%, and in ACA Marketplace plans, about 43%.6KFF. Prior Authorization Metrics Provide New Insights into Insurer Practices, but Gaps Remain Those are remarkably high overturn rates. They suggest that a substantial number of initial denials are overturned once more documentation is provided or the case gets a closer look.
The catch is that very few people actually appeal. Research shows that denials are rarely challenged in Medicare Advantage, Medicaid, or ACA Marketplace plans.6KFF. Prior Authorization Metrics Provide New Insights into Insurer Practices, but Gaps Remain The appeals process is complicated and time-consuming for both providers and patients, and many people simply accept the denial or switch to a different, insurer-preferred treatment. If you receive a denial, asking your doctor’s office to file an appeal is one of the most effective things you can do. Many offices have staff experienced with the appeals process and know how to frame the clinical justification in terms the insurer’s reviewers respond to.
Peer-to-Peer Review
When an initial PA request is denied, your doctor can sometimes request a peer-to-peer review, which is a phone conversation between your treating physician and a physician working for the insurance company. In theory, this allows for a clinical discussion where your doctor can explain the nuances of your case. In practice, it often feels like a bureaucratic hurdle that delays care without adding much value.
A study of peer-to-peer reviews for CT and MRI denials in orthopedic patients found that about 95% of requests were ultimately approved after the review. The median time from the initial office visit to the peer-to-peer call was 9 days, and the median time from the visit to the patient actually getting their imaging appointment was about two weeks.7PubMed. Nearly All Peer-to-Peer Reviews for CT and MRI Prior Authorization Denials for Orthopedic Specialists Are Approved Among the imaging studies that were completed after approval, roughly three-quarters confirmed the diagnosis the orthopedic surgeon had suspected. The reviewing physicians were always doctors, but none of them were orthopedic surgeons, and about 28% had not reviewed the patient’s clinical notes before the call.7PubMed. Nearly All Peer-to-Peer Reviews for CT and MRI Prior Authorization Denials for Orthopedic Specialists Are Approved When nearly every case gets approved anyway and the imaging usually confirms what the specialist already suspected, the peer-to-peer step looks less like quality assurance and more like a speed bump.
How Delays Affect Your Health
The most serious concern about pre-authorization is that it can delay or block care in ways that cause measurable harm. A systematic review synthesizing evidence from 25 studies found that PA requirements were associated with care delays, disease worsening, preventable hospitalizations, prolonged hospital stays, and lower rates of disease-free survival across multiple specialties including oncology, cardiology, behavioral health, and pediatrics.8PubMed. Adverse effects of health plan prior authorization on clinical effectiveness and patient outcomes: A systematic review For neurologic medications specifically, delays in care and increases in disease activity were the most commonly reported consequences for patients.5JAMA Neurology. Barriers and Consequences of Prior Authorization for Neurologic Medications: A Scoping Review
It is worth noting that the picture is not entirely one-sided. A study of diabetes medications found that patients who went through the PA process and ultimately received their medication still had meaningful improvements in blood sugar control. Their average HbA1c dropped by about 0.9%, which was comparable to patients who got the medication without PA and better than patients who received no medication at all.9PubMed. Prior authorization for diabetes medications: Clinical outcomes and health disparities For patients who made it through the process, the medication worked as expected. The concern is about the patients who drop out along the way or whose conditions worsen while they wait.
The Cancer Care Experience
Cancer care is where the tension between cost control and timely treatment becomes most acute. Pre-authorization for cancer drugs, imaging, and procedures can feel especially high-stakes when treatment windows are narrow and the disease is progressing.
A survey of cancer patients who had experienced PA found that about 69% reported delays in their care. Among those delayed, nearly three-quarters waited two or more weeks, and a third waited a month or longer. About 22% of respondents did not receive the care their oncology team recommended, either because delays forced a change in treatment plans or because the request was outright denied.10JAMA Network Open. The Patient Experience of Prior Authorization for Cancer Care Another 10% got their recommended treatment but had to pay out of pocket. Most patients rated the overall PA experience as “bad” or “horrible,” and self-reported anxiety during the PA process was roughly double their usual anxiety levels.10JAMA Network Open. The Patient Experience of Prior Authorization for Cancer Care
The damage extends beyond the clinical. About 89% of cancer patients surveyed said PA made them trust their insurance company less, and 83% trusted the health care system less overall.10JAMA Network Open. The Patient Experience of Prior Authorization for Cancer Care Qualitative research with cancer patients identified themes of confusion, compounded burdens, and a sense that the system was fundamentally broken, with patients describing PA as adding administrative, psychosocial, and financial weight on top of an already overwhelming diagnosis.11PubMed Central. Patient Perspectives on Prior Authorization for Cancer Care
In pediatric oncology, a multi-institutional study found that 56% of enrolled patients faced at least one medication PA. About half of those were for supportive care medications rather than the cancer treatment itself. Care was delayed in about 22% of cases, with waits ranging from 1 to 21 days, and resolving each PA required anywhere from 5 to 240 minutes of staff time.12PubMed Central. Feasibility of Multi-Institutional Data Collection for Medication Prior Authorization in Pediatric Oncology
Racial and Insurance-Based Disparities
Pre-authorization does not land equally on everyone. Research is beginning to reveal patterns in who faces more PA hurdles and who gets denied more often. A study of advanced shoulder imaging found that about 90% of MRI orders required PA. African American patients were roughly 1.6 times more likely to face denials compared to white patients, and Hispanic patients also experienced higher denial rates.13PubMed. The rates and implications of prior authorizations for advanced shoulder imaging Insurance type mattered too: commercial insurance and Medicaid plans had higher denial rates than traditional Medicare.13PubMed. The rates and implications of prior authorizations for advanced shoulder imaging
In gynecologic oncology, having Medicare Advantage was associated with a 76% increased risk of encountering PA compared to traditional Medicare, and patients of Asian descent had a 60% increased risk of experiencing PA. For imaging specifically, those disparities were even more pronounced, with Medicare Advantage patients facing roughly three times the risk of PA compared to traditional Medicare enrollees.14PubMed Central. Insurance and racial disparities in prior authorization in gynecologic oncology These findings are early, and the mechanisms behind the disparities are not fully understood, but they raise questions about whether the administrative machinery of PA disproportionately burdens some patient populations.
Step Therapy and “Fail First” Rules
A related but distinct tool that often gets lumped in with pre-authorization is step therapy, sometimes called “fail first.” Under step therapy, your insurer requires you to try a cheaper or older medication before it will cover the one your doctor originally prescribed. If the first-line drug does not work or causes side effects, you can then “step up” to the preferred medication.
Step therapy is a form of utilization management that aims to encourage cost-effective treatments. It can make sense in situations where a generic drug works just as well as a brand-name alternative for most people. But for patients with conditions where time matters or where a doctor has good clinical reasons for starting with a particular drug, step therapy adds delays and requires patients to endure a treatment their doctor did not think was the best option.15PubMed Central. Analyzing the Benefits and Costs of the Safe Step Act on Patients, Physicians, and Insurers Legislative proposals like the Safe Step Act aim to create exemptions for patients who have already tried and failed on the insurer’s preferred drug, or whose condition is serious enough that stepping through lower-tier treatments could cause harm. Insurers argue that weakening step therapy could drive up premiums and reduce their negotiating leverage with drug manufacturers.15PubMed Central. Analyzing the Benefits and Costs of the Safe Step Act on Patients, Physicians, and Insurers
Gold Carding
One reform gaining traction is “gold carding,” which exempts doctors with consistently high PA approval rates from having to submit PA requests at all. Texas passed a gold card bill in 2022 that exempts physicians with a 90% or higher approval rate from future PA for a minimum of six months on qualifying services. Doctors do not have to apply for the exemption. Instead, health plans review their data and notify providers who meet the threshold. After each six-month review period, providers can be added or removed based on their updated approval rates.16PubMed Central. Gold Carding Policies Reducing the Barriers Between Payers and Providers
The logic is straightforward: if a doctor’s requests are approved the vast majority of the time, requiring them to go through the PA process for every case is waste without meaningful benefit. Several other states have introduced or passed similar legislation. Gold carding does not eliminate PA. It targets the low-hanging fruit of unnecessary friction by carving out the providers who have demonstrated they order appropriate care consistently.
AI and the Automation of Decisions
Both insurers and provider organizations are increasingly turning to artificial intelligence tools to handle prior authorization and claims processing.17PubMed. The AI Arms Race In Health Insurance Utilization Review: Promises Of Efficiency And Risks Of Supercharged Flaws On the provider side, AI can help assemble the documentation and clinical justification needed for a PA submission, potentially saving staff time. On the insurer side, AI can process incoming requests faster than human reviewers.
The risk is that AI can also scale the system’s existing problems. Reports of AI-assisted blanket denials of coverage have increased in recent years, particularly in Medicare Advantage plans. These denials have drawn class action lawsuits, congressional investigations, and criticism that automated systems are rejecting claims without meaningful clinical review.18PubMed Central. Medicare advantage becoming a disadvantage with use of artificial intelligence in prior authorization review The concern is not that AI is being used, but that it could supercharge the same flaws that already plague the system: denying care that should be approved, without adequate human oversight, and at a much faster rate than any human reviewer could.
Federal regulators have begun pushing back. CMS finalized a rule requiring certain insurers to adopt standardized electronic PA processes and to provide faster decision timelines, with the goal of reducing the administrative friction for both providers and patients. Whether these measures keep pace with the speed of AI adoption on the insurer side remains an open question. For now, if you receive what looks like an automated denial, the same advice applies: appeal it, and ask your doctor’s office to escalate with clinical documentation. The overturn rates suggest the effort is frequently worthwhile.