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Appeals2026-07-234 min read

"Not Medically Necessary" Is Not a Medical Opinion

If your claim came back stamped "not medically necessary," it is easy to read those three words as a verdict — as if a physician reviewed your case and decided your care was not warranted.

That is almost never what happened.

"Not medically necessary" is a coverage term, not a clinical one. It usually means the request did not match the checklist your plan uses to approve that drug or service — a checklist written before anyone knew your name. Often no one on the plan's side examined your chart in any depth. Sometimes the person who signed the denial does not practice in the specialty your care falls under.

So the phrase is not the end of the conversation. It is the plan telling you which box it needs checked.

What actually turns this denial around

A general appeal says "please reconsider." A strong response to a medical-necessity denial does something narrower and more powerful: it answers the plan's own criteria, point by point, in your prescriber's words.

That document has a name — a Letter of Medical Necessity. At its core it does four things:

  • Names the exact service or drug that was denied, with the codes and dates from your denial letter, so there is no confusion about what is being appealed.
  • States the diagnosis and the clinical reasoning — why this care, for you, now. This is your prescriber's territory, not yours.
  • Meets the plan's criteria head-on. If the plan requires that you tried other options first, the letter documents what you tried and what happened. If it requires a specific test result or diagnosis, the letter points to where that lives in your record.
  • Cites the standard. Established clinical guidelines or the drug's own labeling carry weight, because they show the request is not unusual — it is standard care.
  • The letter comes from your prescriber. But you are the one who makes sure it gets requested, that it answers the actual reason on your denial, and that it arrives before your deadline.

    Why this is worth the effort

    Fewer than 1% of denied claims are ever appealed (KFF). Yet on Medicare Advantage, when patients do appeal, 82% of denials are overturned (Stanford/KFF). A denial is frequently a first answer, not a final one — and "not medically necessary" is one of the most reversible reasons there is, precisely because it comes down to matching evidence to a checklist.

    The hard part is knowing which checklist, and which evidence.

    That is the part Ellen was built for. When you tell Ellen what was denied, it reads the reason, finds your plan's own policy for that drug or service, shows you exactly which criteria the plan is measuring against, and helps you and your prescriber assemble a response that speaks to those criteria — before the clock runs out.

    You do not need a law degree or a medical one. You need to know what the plan is actually asking for.

    Ellen does not provide medical advice. Ellen helps you understand your coverage and organize your own appeal. Decisions about your care belong to you and your clinician.

    Sources: Kaiser Family Foundation (KFF), analysis of ACA marketplace claim denials and appeal rates (fewer than 1% of denied in-network claims appealed). Stanford/KFF analysis of Medicare Advantage appeals (82% of appealed denials overturned).

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