Can I take a deduction for items given away during a sale in my online store?

[StarWarsGeek]

Let's say I'm having a Buy 1 Get 1 Free sale in my eBay store (which is something that I often do at certain times when I need to generate some business). So I sell a $25 item and the buyer receives a second $25 item free of charge. Can I take a "loss" of $25 for the item that I gave that customer during the B1G1 sale? Or would I just deduct the cost of that item? And where would I report this in the TurboTax reporting? Thanks in advance! 

[Bsch4477]

If you are self employed you will complete Sch C where you enter income and expenses. 

[Mike9241]

if you took a deduction when you purchased the item you're giving away free, you can't deduct it again.

if you account for inventory you automatically get the deduction because the cost of the second item is no longer included in ending inventory.