The causes of black scabs on the feet of the elderly include pigmentation spots, melanoma, eczema, tinea pedis, etc. Treatment includes medication and surgery. 1. Pigmented spots: if the melanocyte proliferation is triggered by various factors, at this time, you can give tranexamic acid, vitamin C and other medications. 2. Melanoma: For black scabs caused by abnormal proliferation of melanocytes, surgical treatment such as melanoma excision can be given at this time. 3. Eczema: when the skin is attacked by inflammatory factors, it is necessary to give anti-inflammatory treatment with drugs such as prednisone and halometasone. 4. Tinea pedis: when the foot is infected by fungus, the fungus will damage the skin leading to the production of black spots, at this time you need to give fluconazole and other drugs to sterilize the treatment. Finally, the phenomenon of black scabs on the feet of the elderly, please consult a doctor in time, the above drugs must be used under the guidance of a physician.