Does anyone have any insight on billing Retacrit 60,000 units? We are encountering some issues. We initially billed 1000 units of Retacrit X60; however, we received denials due to an NDC issue, and the insurance would separate them and not pay for the 20 units. So we decided to separate the billing like this... Retacrit X40 and Retacrit X 20, and now Medicare only paid for the 20, and states the 40 is not payable because..."The benefit for this service was included in payment/allowance for another procedure/service already adjudicated". I can append modifier 51 to one of the charges; however, codify says that would be for private payers. Any help would be greatly appreciated. I will try to call Noridian/Medicare, it's just that sometimes you get push back, or the rep is annoyed with you, or they don't know or have an answer for you.