As far as I know, there's no way to recycle a flexpen. I even disassembled one to see if I could reuse it. No such luck (and it was a glassy mess!). You can get re-fillable metal pens - Novopen Jr. and Novopen 3 - and use small penfill cartridges for Novolog and Levemir. Much less waste. I wish this was the standard.