Glossary
Pharmacy Prior Authorization
A pre-approval requirement Express Scripts imposes on certain drugs before TRICARE Pharmacy will pay.
Also known as: pharmacy PA, drug prior auth
Quick answer
Pharmacy prior authorization (PA) is a coverage-control requirement on selected drugs — usually high-cost brands, drugs with abuse potential, or drugs with safer first-line alternatives. The prescriber submits clinical justification to Express Scripts; once approved, the drug fills at standard copay.
Why it matters
Without PA, the pharmacy claim rejects and the patient faces full cash price or no fill. With PA in hand, the drug fills at the appropriate tier copay.
When you'll encounter it
First fill of selected drugs (eg. some weight-loss agents, biologics, opioids beyond duration limits, certain off-label uses).
Impact on Medicare
None — Express Scripts adjudicates entirely.
Impact on TRICARE For Life
Once approved, drug fills at standard formulary copay through any TRICARE Pharmacy access point.
Impact on Medicare Advantage
MA-PD plans also use PA, often with different (sometimes stricter) criteria. PA approved by one system does not transfer to the other.
Military-specific context
Forms and clinical criteria are published at militaryrx.express-scripts.com/prior-authorization. Most decisions return in 72 hours; urgent decisions in 24.
Common misconceptions
- "PA denial means TRICARE will never cover the drug." — PA decisions can be appealed; many denials are reversed with stronger clinical documentation.
Common mistakes to avoid
- Leaving the pharmacy without telling the prescriber a PA is needed.
- Paying cash to avoid the PA process when the drug would have been covered.
Real-world scenario: A retiree is prescribed Ozempic for type 2 diabetes.
First fill rejects pending PA. The endocrinologist submits documentation of failed metformin therapy. Within 48 hours PA is approved; the drug fills at the formulary brand copay.
What should I do?
- 1If a fill rejects for PA, call the prescriber the same day and ask them to submit it.
- 2Use Express Scripts' PA form library to give the prescriber the exact form needed.
- 3If the PA is denied, request the appeal instructions in the denial letter.
Continue learning
— suggested by the knowledge graph- Prescription drug coverage under TRICARE For LifeWhy TFL beneficiaries use TRICARE Pharmacy (Express Scripts), not Medicare Part D — and how the four pharmacy options compare.
- How Medicare and TRICARE For Life claims are paidThe mechanics of the Medicare-to-TFL crossover system — what providers do, what WPS does, and what to do if a claim gets stuck.
- What is TRICARE For Life? The complete guide for retired militaryThe Medicare-wraparound benefit you earned through service — what it covers, who qualifies, what it costs, and how it activates.
- How Medicare and TRICARE For Life work togetherThe exact mechanics of who pays first, who pays second, and what you owe — for every common care scenario.
- Non-Network PharmacyA civilian pharmacy that is NOT contracted with Express Scripts — highest cost and usually requires you to pay up front and file a claim.
- Overseas Pharmacy ClaimsHow TFL beneficiaries fill prescriptions outside the US — usually pay up front and file for reimbursement.
- Brand-Name DrugsFDA-approved drugs sold under a manufacturer's proprietary name — middle copay tier on the TRICARE formulary.
- Creditable Drug CoveragePrescription drug coverage that CMS certifies is at least as good as standard Medicare Part D — including TRICARE Pharmacy and VA Pharmacy.
- Express ScriptsThe pharmacy benefit manager that administers the TRICARE Pharmacy Program, including TFL home-delivery and retail-network prescriptions.
- Generic DrugsChemically identical, FDA-approved equivalents of brand-name drugs — the lowest copay tier under TRICARE Pharmacy.
- Medicare Part D and TFLWhy TFL beneficiaries do not need (and usually should not enroll in) a standalone Medicare Part D plan.
- What is a pharmacy prior authorization?Some drugs (high-cost specialty, opioids, certain brand-names) require Express Scripts to approve before TRICARE will pay. Your doctor submits the request.
- Who pays first, Medicare or TRICARE For Life?Medicare pays first for any service it covers. TFL pays second. The claim usually crosses over automatically — you should never pay out of pocket up front.
- Is there an enrollment fee for TRICARE For Life?No. TFL has no enrollment fee and no monthly premium. The only premium you pay is for Medicare Part B.
- Should I enroll in Medicare Part D?No, for almost every TFL beneficiary. TRICARE Pharmacy (Express Scripts) is creditable coverage and cheaper than most Part D plans. Adding Part D usually costs more without adding benefit.
- What if my drug isn't on the TRICARE formulary?Non-formulary drugs cost more. Your doctor can request a medical-necessity exception so it's covered at the formulary copay.
Related glossary terms
Related Official Resources
Continue learning straight from the source. Every link below goes to an official government or DoD resource.
Last reviewed January 2026 against the 2026 Medicare & You and TRICARE For Life handbooks.