Thanks for asking at Healthcare Magic. I read your question and I understand your concern. La 12 can t prevent foot from gangrene. It is basically vitamin B12 that helps in regeneration of damaged nerve fibres. As foot ulcer and gangrene in diabetic foot has two main reasons. 1. Neuropathy loss of sensations and weakness of muscles; that causes change in foot contour and make foot insensitive to touch and painful stimuli 2. Ischemia the decrease in blood flow to tissues due to accelated atherosclerosis of arteries of foot like dorsalis pedis and posterior tibial artery Both these factors causes ulcer formation. You need to have regular checkup of your foot. Use mirror to see the soles. Cut the nails in U shape. Use pressure offloading shoes. Don t walk barefoot. Always wipe your feet after washing. Tightly controlled your blood sugar, use La 12 (keep an eye on potassium level) and Pregabalin (lyrica) for neuropathy, statins (Rosuvastatin), Aspirin and sometimes pletal (cilastazole) for ischemia. Always treat infection in early stages. Hope it helps best. Don t forget to rate this answer. Take your best care. Regards Dr Ejaz