Glossary
Prior authorization
Prior authorization is approval a health plan requires before it will cover certain services, tests, or drugs. It is common on Medicare Advantage plans and for some Part D drugs; Original Medicare uses it far less. Your provider submits the request, and care can be delayed if it is not approved first.
The idea is that the plan checks whether a service is medically necessary before agreeing to pay. In practice it means an extra step: your doctor sends documentation, the plan reviews it, and only then is the care covered. If the plan denies the request, you can appeal.
How often a plan uses prior authorization is worth weighing when you choose coverage. Original Medicare requires it for very few services, while Advantage plans vary widely in how much they use it.
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