Mecosys 500mcg Injection is a man-made form of vitamin B12. It is used to treat deficiency of vitamin B12 in the body. Vitamin B12 is important for growth, cell reproduction, blood formation, and protein and tissue synthesis. It also helps to treat anemia, fatigue, and numbness or tingling in the hands and feet. Mecosys 500mcg Injection should be used exactly as prescribed by the doctor. Follow all directions on the prescription label and read all medication guides before use. You should use it regularly and at a fixed time each day to get the most benefit from it. This medicine may be only part of a complete program of treatment that also includes making changes to your diet and taking other medicines and supplements. Learn about the foods you should eat to make sure you get enough vitamin B12 in your diet. Mecosys 500mcg Injection is generally safe and does not usually cause any common side effects. Some medicines can decrease the absorption of vitamin B12, let your doctor know all other medicines you are taking to make sure you are safe. To make sure it is safe for you, before using the medicine let your doctor also know if you have any medical conditions such as Leber's disease, liver disease, or kidney disorder.