Physicians bill for Unna Boot application using code 29580.  The supply code is A6456, Zinc paste impregnated bandage, non-elastic, knitted/woven, width greater than or equal to three inches and less than five inches, per yard.  Notice that the code unit is 1 for one yard.  Bill for both on the same day.

Unna boot application and debridement are bundled together, when provided to the same wound. 

An E/M service is probably billable the first time the physician sees and evaluates the patient for that condition, and applies the Unna Boot. Be careful about follow up services.  If the Unna Boot application was planned at a previous visit, there may not be the medical necessity for an E/M service.  If a separate wound or problem is addressed, it is more likely that a separate E/M service is required.