Skip to main content

Letter of Medical Necessity

Meaning

A Letter of Medical Necessity (LMN) is a formal, detailed, and evidence-based document written by a prescribing healthcare provider to an insurance company or third-party payer to justify the clinical requirement for a specific treatment, medication, or medical device. This document asserts that the requested intervention is essential for the patient’s health, aligns with current standards of care, and is not merely for convenience or cosmetic purposes. It is a critical administrative step in securing coverage for specialized or non-formulary hormonal therapies.