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A - Commonly Furnished in Physicians' Offices
Services and supplies commonly furnished in physicians' offices are covered under the incident to provision. Where supplies are clearly of a type a physician is not expected to have on hand in his/her office or where services are of a type not considered medically appropriate to provide in the office setting, they would not be covered under the incident to provision.
Supplies usually furnished by the physician in the course of performing his/her services, e.g., gauze, ointments, bandages, and
oxygen, are also covered. Charges for such services and supplies must be i
ncluded in the physicians' bills. (See §50 regarding coverage of drugs and biologicals under this provision.) To be covered, supplies, including drugs and biologicals, must represent an expense to the physician or legal entity billing fir he services or supplies. For example, where a patient purchases a drug and the physician administers it, the cost of the drug is not covered. However, the administration of the drug, regardless of the source, is a service that represents an expense to the physician. Therefore, administration of the drug is payable if the drug would have been covered if the physician purchased it.
http://www.cms.hhs.gov/manuals/Downloads/bp102c15.pdf