You can take methylcobalamin for fatty liver, but methylcobalamin cannot treat fatty liver. When you have fatty liver, you should seek medical advice from your doctor. Fatty liver is a lesion caused by excessive fat accumulation in liver cells due to various reasons. Patients with fatty liver are advised to control their diet and avoid spicy, stimulating, fried and barbecued foods; increase exercise to promote fat metabolism; and take lipid-lowering medications, such as atorvastatin and simvastatin, to alleviate the condition. Methylcobalamin is an endogenous coenzyme, a derivative of vitamin B12, which can participate in the production of human nerve cells and red blood cells, and has the role of repairing and nourishing nerves. It is commonly used clinically in the treatment of peripheral neuropathy, such as peripheral neuritis, neuralgia, neurological disorders, etc. It can also be used in the treatment of megaloblastic anemia, and cannot be used in the treatment of fatty liver. Long-term use of methylcobalamin can cause adverse reactions, such as dyspepsia, nausea and vomiting and other gastrointestinal symptoms; allergic patients may also experience allergic symptoms, such as rashes, fever and so on. Patients with fatty liver need to use methylcobalamin under the guidance of a doctor, not without authorization, so as not to delay the condition.