---
name: "Write a persuasive prior-authorization / medical-necessity l"
description: "Write a persuasive prior-authorization / medical-necessity letter to an insurer. Use when asked to write a prior authorization letter, a letter of medical necessity, or to appeal a denied treatment/medication/procedure. Produces a structured letter — patient and request, clinical justification tied to guidelines, treatments tried, and the specific approval asked for — ready for clinician review and signature."
---

# Prior Authorization Letter Skill

A prior-auth or medical-necessity letter succeeds when it connects *this patient's* clinical facts to the
insurer's coverage criteria — clearly, with evidence, and with the exact request spelled out. This skill
structures that argument so the reviewer can approve it quickly, and so an appeal addresses the stated denial
reason head-on.

> **Clinical-safety note:** this is a documentation aid, **not medical advice**. The clinical justification must
> reflect the treating clinician's judgement and the patient's actual record; the clinician must review, verify,
> and sign before submission. Do not invent diagnoses, codes, history, or evidence.

## Working from a brief

Given the treatment and a diagnosis, **produce the full letter anyway** — structure the argument and insert the
standard elements, marking patient-specific facts (codes, dates, prior treatments) to be confirmed rather than
inventing them. For an appeal, infer and directly rebut the likely denial reason if it's stated. Never fabricate
clinical history or citations.

## Required Inputs

Ask for these only if they aren't already provided (else mark to confirm):

- **Patient & policy** — patient identifiers and insurance/policy details (as provided).
- **The request** — the specific medication/procedure/service, with codes (CPT/HCPCS/ICD-10) if available.
- **Clinical justification** — diagnosis, severity, relevant history, and why this treatment is medically necessary.
- **Prior treatments** — what's been tried and failed/contraindicated (step-therapy history).
- **If an appeal** — the denial reason given by the insurer.

## Output Format

### Letter of Medical Necessity / Prior Authorization

- **Header** — date, insurer/UM department, patient name, policy/member ID, and the requesting clinician.
- **Re:** the specific request and relevant codes (diagnosis + procedure/drug).
- **1. Request** — one sentence stating exactly what authorization is sought.
- **2. Patient clinical picture** — diagnosis, severity, functional impact, and pertinent history (verified facts only).
- **3. Medical necessity** — why this treatment is necessary for this patient, tied to recognised clinical
  guidelines/evidence and the insurer's likely coverage criteria.
- **4. Prior treatments tried** — the step-therapy history: what was tried, the outcome, and why alternatives are unsuitable.
- **5. Requested action** — the explicit approval asked for, and the clinician's offer to provide records or discuss.
- **Signature block** — clinician name, credentials, contact.

For an appeal, add a section that **quotes the denial reason and rebuts it specifically**.

Close with a list of **facts to confirm** before sending and a clinician-sign-off reminder.

## Quality Checks

- [ ] The exact request (with codes where available) is stated unambiguously up front
- [ ] Medical necessity is tied to recognised guidelines/criteria, not just assertion
- [ ] Step-therapy / prior-treatment history is documented (what was tried and why it failed/is unsuitable)
- [ ] For an appeal, the specific denial reason is quoted and directly rebutted
- [ ] No clinical fact, code, or citation is invented — unverified items are flagged to confirm
- [ ] The letter is ready for clinician review and signature (signature block included)

## Anti-Patterns

- [ ] Do not invent diagnoses, codes, dates, prior treatments, or evidence to strengthen the case
- [ ] Do not be vague about the request — name the exact service/drug and codes
- [ ] Do not ignore the stated denial reason in an appeal — address it head-on
- [ ] Do not present this as medical advice or submit without clinician review and signature
- [ ] Do not pad with generic boilerplate that buries the patient-specific justification

## Based On

Utilization-management correspondence practice — medical-necessity argumentation tied to coverage criteria, step-therapy documentation, and targeted appeals.
