Hi, thanks for your question. I have read it and understand your concern The benefits of taking Invokana outweigh the risks associated with this drug in majority of patients. One study has shown that this medication increases the risk of amputation by two fold in high risk patients. While 12 other clinical trials did not find any increased risk. So there is no need to be unnecessarily alarmed at the moment. Please make sure that you are taking enough fluids to remain hydrated while on this drug. However, if you develop an ulcer, pain, discolouration or tenderness in your feet or have a history of amputation or gangrene, then you should not be using this medication. Diabetic patients are are at increased risk of amputations, therefore you should be regularly taking preventive foot care. If your toenail doesn’t look healthy, then I would recommend that you see your doctor who may discontinue this drug and start another one. Hope this helps. And please feel free to contact me in case of any confusion.