CMS Pub. 100-04, ch. 20, § 100.2.2.1

Recertifications of Medical Necessity for PEN

(Rev. 1, 10-01-03)

A certification for PEN therapy must accompany the initial claim submitted. The initial

certification is valid for six months. DME MACs 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).