Methylcobalamin tablets are best taken within half an hour after a meal. Methylcobalamin Tablet is an endogenous vitamin B₁₂, which can promote nerve tissue repair and inhibit neurodegeneration, and is mainly used for patients with megaloblastic anemia, neuritis, and diabetes mellitus complicated with peripheral neuropathy. Methylcobalamin tablets are contraindicated in patients with allergies. As nausea, vomiting, stomach discomfort and other symptoms of gastric mucous membrane damage may occur after taking methylcobalamin, it is generally recommended to take methylcobalamin tablets within half an hour after meals, which can reduce the gastrointestinal adverse reactions brought about by the drug. In addition to gastrointestinal discomfort, methylcobalamin tablets may also cause headache, fever, fatigue, easy sweating and other adverse reactions, which is prohibited for patients who are allergic to this drug. Therefore, patients who need to take methylcobalamin tablets should go to the hospital in time, under the guidance and advice of the doctor to take the drug, to reduce the occurrence of adverse reactions. Adverse drug reactions after taking the medication should also seek medical attention in time.