Scheduling and Documenting Certifications and Recertifications of Medical Necessity for PEN

A certification for PEN therapy must accompany the initial claim submitted. The initial certification is valid for six months. Contractors establish the schedule on a case-by-case basis for recertifying the need for PEN therapy. A change in prescription for a beneficiary past the initial certification period does not restart the certification process.

A period of medical necessity ends when PEN services are not medically required for 2 consecutive months. The entire certification process, if required, begins after 2 consecutive months have elapsed.

A revised certification or a change in prescription may impact on the payment levels of PEN services. A revised certification is appropriate when there is a change:

• In the treating physician's orders in the category of nutrients and/or calories prescribed;

• By more than one liter in the daily volume of parenteral solutions;

• From home-mix to pre-mix or pre-mix to home-mix parenteral solutions;

• From enteral to parenteral or parenteral to enteral therapy; or

• In the method of infusion (e.g., from gravity-fed to pump-fed).

DMERC Review of Initial PEN Certifications

In reviewing the claim and the supporting data on the CMN, the DMERC compares certain items, especially pertinent dates of treatment. For example, the start date of PEN coverage cannot precede the date of physician certification. The estimated duration of therapy must be contained on the CMN. This information is used to verify that the test of permanence is met. Once coverage is established, the estimated length of need at the start of PEN services will determine the recertification schedule. The information shown on the certification must support the need for PEN supplies as billed. A diagnosis must show a functional impairment that precludes the enteral patient from swallowing and the parenteral patient from absorbing nutrients.

Initial assigned claims with the following conditions are denied without development:

• Inappropriate or missing diagnosis or functional impairment;

• Estimated duration of therapy is less than 90 consecutive days;

• Duration of therapy is not listed;

• Supplies have not been provided;

• Supplies were provided prior to onset date of therapy; and

• Stamped physician's signature.

Unassigned claims are developed for missing or incomplete information.


A. Revised Certifications/Change in Prescription

A revised certification is required when:

• There is a change in the attending physician's orders in the category of nutrients and/or calories prescribed;

• There is a change by more than one liter in the daily volume of parenteral solutions;

• There is a change from home-mix to pre-mix or pre-mix to home-mix parenteral solutions;

• There is a change from enteral to parenteral or parenteral to enteral therapy; or

• There is a change in the method of infusion (e.g., from gravity-fed to pump-fed).

The PEN payments are not adjusted unless a revised or renewed certification documents the necessity for the change. Payment levels for the most current certification or recertification may not be changed unless a prescription change is documented by a new recertification.

The DMERC may adjust the recertification schedule as needed.

Completion of the Elements of PEN CMN - Part 3

Enteral nutrient categories III through VI require additional medical justification for coverage. These categories represent formulas for special needs or use.

• Category III (code B4153): hydrolyzed protein/amino acids. These products contain a high nitrogen availability as a result of chemical treatment to reduce high molecular protein compounds into smaller molecules and amino acids that are easier to digest.

• Category IV (code B4154): defined formulas for special metabolic needs and conditions such as abnormal glucose tolerance, renal disease, liver disease, HIV, respiratory insufficiency, and malnutrition.

• Category V (code B4155): modular components


• Category VI (code B4156): standardized nutrients. These products contain low residue ingredients.

If the patient exhibits a problem with any particular formula in Nutrient Category I (HCPCS B4150) or II (HCPCS B4152), the physician must document the unfavorable events that resulted in prescribing a higher category formula.

Generally, daily enteral intake of 750 to 2,000 calories is considered sufficient to maintain body weight. Patients with medical complications may require an intake outside the range. The attending physician must document the reason for prescribing less than 750 calories per day or more than 2000 calories per day.

Enteral nutrition may be administered by syringe, gravity, or pump. The attending physician must specify the reason that necessitates the use of an enteral feeding pump. Some enteral patients may experience complications associated with syringe or gravity method of administration. Contractors provide coverage for enteral pumps if the medical necessity is documented by the attending physician on the CMN. Examples of circumstances that indicate the need for a pump include, but are not limited to:

• Aspiration or Dumping Syndrome;

• Severe diarrhea remedied by regulated feeding;

• Insulin-dependent diabetics who require a flow rate of less than 100cc's per hour for proper regulation of nutrients;

• Patients with congestive heart failure who require a pump to prevent circulatory overload; or


The DMERC reviews the claims to ensure that the equipment for which payment is claimed is consistent with that prescribed (e.g., expect a claim for an I.V. pole, if a pump is used).

5. Attending Physician's Signature and Identification - A handwritten, original signature and date must be on each certification. The form must be dated to show reasonable association to the dates of active PEN therapy. The full name, address, telephone number (including area code), and Unique Physician Identification Number (UPIN) allows the contractor to determine if the prescriber is authorized to order Medicare services and facilitate claims dependant.

1. PEN Supplier's Identification - The PEN supplier's name, address, telephone number, and PEN identification number must be on each certification. This information allows the contractor to determine if the supplier is authorized to provide PEN supplies and facilitate claims development.

Completion of the Elements of PEN CMN - Part 2

Amino acids serve as a source of protein. Adult parenteral nutrition patients generally need 1 to 1.5 grams of protein per day for each kilogram (2.2 pounds) of body weight. Dextrose concentrations less than 10 percent must be explained by the physician. The physician must document the reason for using more than 12 units (@ 500ml per unit) of lipids per month.

Parenteral nutrition may be either "self-mixed" (i.e., the patient is taught to prepare the nutrient solution aseptically) or "pre-mixed" (i.e., the nutrient solution is prepared by trained professionals employed or contracted by the PEN supplier). The attending physician must provide information to justify the reason for "pre-mixed" parenteral nutrient solutions.

Renal dialysis patients sometimes undergo parenteral therapy to replace fluids and nutrients lost during dialysis. Patients are usually infused less than daily and parenteral feeding is often supplemental and, therefore, not covered as a PEN benefit. The renal dialysis patient must meet all the requirements for PEN coverage. The attending physician must document that the patient, despite the need for renal dialysis, suffers from a permanently impaired functional impairment that precludes swallowing or absorption of nutrients.
For the enteral patient, the attending physician must include the following information on the CMN:

• The name of the nutrient product or nutrient category,

• The number of calories per day (100 calories = 1 unit),

• The frequency per day,

• The method of administration (i.e., syringe, gravity, or pump),

• The route of administration (i.e., nasogastric tube, gastrostomy tube, jejunostomy tube, percutaneous enteral gastrostomy tube, or naso-intestinal tube), and

• The reason for the use of a pump.


Categories of enteral nutrition are based on the composition and source of ingredients in each enteral nutrient product. Category IB of enteral nutrients contains products that are natural intact protein/protein isolates commonly known as blenderized nutrients. Additional documentation is required to justify the necessity of Category IB nutrients. The attending physician must provide sufficient information to indicate that the patient:

• Has an intolerance to nutritionally equivalent (semi-synthetic) products;

• Had a severe allergic reaction to a nutritionally equivalent (semi-synthetic) product; or

• Was changed to a blenderized nutrient to alleviate adverse symptoms expected to be of permanent duration with continued use of semi-synthetic products.

Completion of the Elements of PEN CMN - Part 1

The patient's name, address, and HICN and the nature of the certification (i.e., initial, renewed, or revised) must be entered on all certifications by the supplier, physician, or physician's designated employees. The supplier identifying information is required on all PEN certifications.

All medical and prescription information must be completed from the patient's records by the attending/ordering physician, or an employee of the physician authorized to act on the physician's behalf, and reviewed and signed by the physician.


1. Place of Service - The CMN must identify the site where the patient is receiving PEN services. A patient may receive services at home, in a nursing home setting (e.g., skilled nursing facility), or another site that must be indicated by the supplier/physician.

2. Patient's General Condition - The attending physician must complete information about the patient's age, height, and weight. The general condition of the patient also includes an estimated duration of therapy (i.e., in months, years, or for life), the ambulatory status, and whether the patient is conscious. The physician should also indicate food allergies/sensitivities, other medical treatments, therapies, and/or medical conditions that may affect the patient's nutritional needs.

3. Patient's Clinical Assessment - The attending physician must indicate all the diagnoses related to the PEN therapy and describe the patient's functional impairment of the digestive tract that precludes the enteral patient from swallowing and the parenteral patient from absorbing nutrients. The physician must certify that PEN therapy meets the requirement that a patient is not able to maintain weight and strength due to pathology or nonfunction of the ingestion system and that the enteral therapy serves as the source of nutrition for the patient who has a functioning digestive tract, but whose disability prevents ingestion of sufficient nutrients to the alimentary tract for metabolism. Nutritional supplements for patients capable of ingesting normally, even if required to maintain weight and strength, cannot be covered under the prosthetic device benefit. The physician must have a basis for certifying or recertifying the need for PEN services. The physician is expected to see the patient within 30 days prior to certifying or recertifying PEN services. However, if the physician did not see the patient, he/she must explain why and describe what other monitoring methods were used to evaluate the patient's PEN needs.

4. Patient's Nutritional Prescription - Subsequent to an examination of the patient and/or a review of the patient's medical information, the attending physician must complete the patient's nutritional requirements (prescription) to certify the PEN therapy provided.

For the parenteral patient, the CMN must contain the following information:

• The infusion frequency per week,

• The route of administration,

• A reason for the use of pre-mixed parenteral formulas,

• An explanation for the use of special formulas such as hepatic, renal, or stress

• formulas, and

• The amino acid/dextrose formula components of the parenteral solution mix.

Evidence of Medical Necessity for Parenteral and Enteral Nutrition (PEN) Therapy

The PEN coverage is determined by information provided by the treating physician and the PEN supplier. A completed certification of medical necessity (CMN) must accompany and support initial claims for PEN to establish whether coverage criteria are met and to ensure that the PEN therapy provided is consistent with the attending or ordering physician's prescription. Contractors ensure that the CMN contains pertinent information from the treating physician. Uniform specific medical data facilitate the review and promote consistency in coverage determinations and timelier claims processing.

The medical and prescription information on a PEN CMN can be most appropriately completed by the treating physician or from information in the patient's records by an employee of the physician for the physician's review and signature. Although PEN suppliers sometimes may assist in providing the PEN services, they cannot complete the CMN since they do not have the same access to patient information needed to properly enter medical or prescription information. Contractors use appropriate professional relations issuances, training sessions, and meetings to ensure that all persons and PEN suppliers are aware of this limitation of their role.

When properly completed, the PEN CMN includes the elements of a prescription as well as other data needed to determine whether Medicare coverage is possible. This practice will facilitate prompt delivery of PEN services and timely submittal of the related claim.