How to write a letter of medical necessity: a step by step guide with examples

1. Say who you are (primary care physician, specialist), how long you have known the patient, and the service which you are requesting.
2. State, using the language of the law, why these service is medically necessary. Example: Jane Doe needs special medicine because I expect it to assist her in achieving maximum functional capacity. Using the language of the law is not plagiarism!
3. Use all parts of the legal definition which are relevant to your patient.
4. Expand on each statement to give supporting medical evidence. Evidence can be from your chart, from consultant letters, or from conversations with family member.
5. Specifics which are helpful in expanding on the legal definition:
   • With as much detail as possible, explain how it will prevent an illness or disability. Refer to medical articles or lectures. Review failed treatments. Consider information available to you about the patient, such as compliance with other regimens, family and home supports, or coping skills, which the HMO may not know. Be specific about goals.
   • With as much detail as possible, explain how it will ameliorate the physical, mental, or developmental effects of the patient’s illness. Cite past successes with the treatment. Cite recent medical articles. Include letters from consultants. Review failed treatments and address the HMOs suggested treatments. Be specific about psychological factors that are relevant to your chosen treatment. Provide information you have which a distant administrator may not know.
   • With as much detail as possible, explain how it will assist the patient to maintain functional capacity. Include letters from physical or occupational therapists. Cite conversations with family members or other treating physicians. Include journal references on unusual or new treatment modalities.
6. Conclude with repeating your prescription and the medical consequences which you believe will result if the prescription for medications or services is denied.

• Review previous treatments you have tried, what results they produced, and what led you to change them. Be as specific as possible.
• If the HMO has suggested alternatives, address each one of these without anger. If they seem possible but you consider them to be second or third choice after your recommendation, acknowledge that and explain why.
• If you have had particular success with the treatment you are recommending which the HMO or other physicians might not be aware of, document this success.
• If you would agree with the HMO in general in a case such as this, but feel this is a special situation, acknowledge this and explain the situation. "Ordinarily I only prescribe generic medications but I have been unsuccessful in challenging the patient’s belief that all other medications make her ill."
• If you are seeking approval for durable medical equipment, check the Medicare website or commercial providers to review criteria for durable medical equipment. This will often clarify the standards which are being used, and allow you be more specific about why your patient meets these requirements.
• Carefully consider information available to you, as the person’s physician, which a distant administrator may not have. This includes coping skills, economic situation, availability of home help and support, language or education barriers, transportation barriers, history of compliance or not with past regimens. Be specific about why these are relevant to your request.
• Avoid anger, snide comments, criticism of managed care or the health care system. Be positive and explain why you feel the patient needs what you prescribed.