In normal, healthy individuals, it would be very unlikely to get gangrene. Gangrene essentially is tissue necrosis, in other words, part of your body dies and starts to rot. The body's immune system is very adept and competent at both combating bacteria that may cause tissue death and also at removing dead tissue and then healing around it. It is only when this process fails or is overwhelmed that gangrene can occur. There are a couple of common reasons for this. By far the most common patient population that experiences gangrene are diabetics, especially the poorly controlled ones. This is because diabetes causes damage to the large blood vessels and capillary beds which supply your tissues with much needed oxygen. Without adequate circulation, the tissues often have trouble surviving even at rest, let alone have the strength to survive an infection. In addition, without good capillary beds the body cannot bring the immune cells that are needed to fight an infection into the area where they are needed most. The bottom line is that the body's immune system is very compromised in bad or long-term diabetes, thus we commonly see gangrene in these people.
Other conditions which lead to gangrene are high blood pressure
, peripheral vascular disease, heart disease, severe malnutrition, certain vitamin deficiencies (e.g. scurvy), severe crush injuries, etc. Even so, gangrene is not common in these people, with the exception of those with severe peripheral vascular disease. If you are a diabetic or have one of these conditions you should see your primary care doctor
who may have suggestions for you regarding wound care
and keeping you condition under control. If you don't have one of these conditions, you probably just have an infected toe. Make sure that you clean the wound daily and apply topical over-the-counter antibiotics and keep it covered. And to be safe, please see your doctor about it to make sure it has not progressed to something more substantial.