There is generally little difference between cheap and expensive methylcobalamin tablets as far as efficacy and effectiveness are concerned. Methylcobalamin tablets, the main ingredient of which is methylcobalamin, are mainly used in the treatment of peripheral neuropathy. Because the ingredients of methylcobalamin tablets are relatively fixed, so the selling price is about the same. The difference in price is mainly due to the difference in pricing between brands, pharmaceutical manufacturers, and local pharmacies or platforms. Mecobalamin tablets are also available in different sizes. Commonly available on the market are 7 tablets per board and 10 tablets per board, etc., and the selling price of different sizes may also vary. Common adverse reactions to methylcobalamin tablets include loss of appetite, vomiting and diarrhea. When serious adverse reactions occur, you should seek immediate medical attention. In addition, it is prohibited for people who are allergic to any of the components of the drug; workers engaged in the production of mercury and its compounds should avoid taking it for a long period of time. The drug belongs to the prescription category and medical advice is required before taking it.