What Prior Authorization Is and How the Process Actually Works

Prior authorisation is a condition your insurance plan attaches to certain medications: it will pay, but only after your prescriber submits clinical justification and the plan approves it. The pharmacy cannot complete it, and neither can you. Understanding that ownership is most of the battle, because the commonest cause of a long delay is everyone waiting for someone else to start.

What the plan is actually asking for

The plan wants evidence that this drug, for this person, meets criteria it has written down in advance. Those criteria are specific and usually mundane: a documented diagnosis, a particular test result, a record of which alternatives have already been tried, confirmation that the dose falls in an expected range, or evidence that a specialist is involved.

The criteria exist because the drug is expensive, has a narrower appropriate use than its label suggests, is prone to being prescribed where a cheaper option would do, or carries safety considerations the plan wants documented. Whether any given criterion is reasonable is a fair argument to have. What matters operationally is that the criteria are written, finite, and knowable — your plan will tell you what they are if you ask, and your prescriber’s office can often look them up directly.

Prior authorisation is a coverage gate, not a prescribing restriction. Your prescriber can still write the prescription and you can still fill it by paying the full price. The authorisation determines who pays, not whether the medication is legal or appropriate.

How you find out it is required

Usually you find out when the claim rejects at the pharmacy. The plan’s system returns a message meaning “prior authorisation required,” and the pharmacy tells you the insurance will not pay yet. This is a coverage condition surfacing at the least convenient moment, and it is why what it means when a pharmacy says your claim was rejected is worth reading before it happens to you.

You can also find out in advance, which is much better. Restrictions like this are marked against individual entries in your plan’s drug list — see what a drug formulary is and how its tiers set your cost — so a prescriber who checks the formulary before sending can start the paperwork the same day rather than a week later.

Some prescribing systems now flag the requirement at the moment of writing and let the office submit electronically before you ever leave. Where that happens, the whole delay can compress to hours.

The sequence, and who does each step

Five steps, three parties.

1. The pharmacy tells you it is required, and tells the prescriber. Most pharmacies send a notification automatically. Most, not all — and notifications get missed.
2. The prescriber’s office obtains the plan’s criteria and form. Larger practices have staff who do only this.
3. The office submits clinical documentation to the plan. Electronically where supported, by fax or portal otherwise.
4. The plan reviews and issues a decision. Plans publish a decision window for standard requests and a shorter one for expedited requests where a delay would cause harm. The windows are in your plan documents, and asking for expedited review is a normal request when the situation warrants it.
5. If approved, the pharmacy resubmits the claim. This does not always happen automatically. Sometimes you have to ask.

Step five is the quiet failure point. An authorisation can be approved while the prescription sits untouched at the pharmacy because nobody re-ran the claim. If you were told approval was coming, call the pharmacy rather than waiting for a text.

What makes it slow, and what you can do

Almost every long delay traces to one of four things. Knowing them lets you ask the right question instead of chasing status updates.

• Nobody started it. The pharmacy’s notification did not land, or landed in a queue. Fix: call the prescriber’s office and confirm they have the request, naming the drug and the plan.
• The submission was incomplete. A missing test result or an undocumented previous drug trial sends it back. Fix: ask what the plan asked for.
• It went to the wrong reviewer. Plans sometimes route drug requests through a medical benefit rather than a pharmacy benefit, or vice versa. Fix: ask the plan which benefit the drug is processed under.
• It was approved but not applied. As above. Fix: ask the pharmacy to resubmit.

Two practical habits help. Keep your own short list of medications you have previously tried for the condition, with rough dates and why each was stopped — this is exactly what step-therapy criteria ask for and it is frequently missing from records that span multiple practices. And get the reference number for the request, so every later call starts from a known point rather than a re-explanation.

Approvals are not permanent

Most authorisations carry an expiry, and some carry conditions. An approval may cover a defined period, after which the request has to be renewed. It may cover a specific quantity or strength, so a later dose change triggers a fresh request. It generally does not survive a change of insurance plan, because the criteria belong to the plan and the new one has its own.

Two moments deserve a calendar note: the point in the year when your plan renews, since formularies and criteria change then, and any point at which your prescriber adjusts the dose. Both routinely reset a settled situation.

When it is denied

A denial is the start of a defined process, not the end of the road. There is an internal appeal, an external review beyond that in most cases, and an expedited track where waiting would be harmful. Denials also frequently rest on a fixable gap in documentation rather than a genuine clinical disagreement, which means the second attempt often succeeds where the first did not. What to do when your insurance denies a prescription covers the levels and the paperwork.

If the denial rests on the plan wanting a different drug tried first, that is step therapy rather than a plain refusal, and it has its own exception route — see what step therapy is and why you are told to try another drug first.

While you wait

Ask the pharmacy two things. Whether a short supply can be dispensed to bridge the gap, which is sometimes possible and sometimes not depending on the drug and the plan. And what the cash price is, because for some drugs it is low enough that waiting for an authorisation is not worth it. Neither question undermines the request in progress, and both are ordinary things to ask.