Water for injection is a liquid made by science and technology for human injection, while distilled water is evaporated when water meets heat and cannot be used for medical purposes. Medical sterilized water for injection is distilled water obtained after filtration and sterilization. Distilled water is pure water prepared by distillation. It can be divided into once and many times distilled water. The water is distilled once, the non-volatile components remain in the container and are removed, and the volatile components go into the initial fraction of the distilled water, which is usually collected only in the middle part of the fraction. Water for injection means water that meets the requirements set forth in the Chinese Pharmacopoeia under Water for Injection. Water for injection is water obtained by distillation of distilled water or deionized water, so it is also called redistilled water. Please choose water for injection or distilled water carefully, depending on the specific use.