Question: When we code for drug wastage, I-m always concerned we-ll make an error. I have heard that there is an easy way to accurately calculate wastage. Can you shed any light on this? Kansas Subscriber Answer: The key to accurately calculating drug wastage begins with knowing which drugs are single-dose vials and when you should expect waste to occur. There is a simple formula you can use that applies to all drugs from a single-dose vial: Step 1: Add the dose given and the amount wasted to determine the total amount. Step 2: Divide the total amount by the drug's billable unit to determine the quantity of units you should bill Example: You-re coding for an encounter in which the provider administers 125 mg of oxaliplatin (J9263, Injection, oxaliplatin, 0.5 mg), using three 50-mg single- dose vials. Here's how you-d calculate your wastage: Step 1: 125 (mg given) + 25 (mg wasted) = 150 (total mg) Step 2: 150 (total mg) divided by 0.5 mg (oxaliplatin's billable unit) = 300 (total units billed) Experts note: According to the CMS Web site, if you use a single-dose vial on multiple patients, you should assign the remaining waste to the last patient on whom you use the single-dose vial. Remember: When you only use the same vial on a single patient, you will also need to bill it entirely to that single patient. Warning: You should never report waste on multi-dose vials. Fore more info: The examples cited above were used by Lisa Martin, CPC, CPC-IM, CPC-I, during her recent presentation "Increase Your Charge Capture for Oncology Drugs" for The Coding Institute, available at
http://www.codingconferences.com/oncology08cds_doc_books.htm. Bonus: When coding for drug wastage, another good tool to have handy is modifier JW (Drug amount discarded/not administered to any patient). According to CMS, "When processing all drugs except those provided under the Competitive Acquisition Program for Part B drugs and biologicals (CAP), local contractors may require the use of the modifier JW to identify unused drug or biologicals from single-use vials or single-use packages that are appropriately discarded. This modifier will provide payment for the discarded drug or biological." You can find more information on processing claims involving drug wastage on the CMS Web site at
http://www.cms.hhs.gov/manuals/downloads/clm104c17.pdf.