The functions of saline include dissolving drugs, maintaining fluid balance, and cleaning wounds. 1. Dissolve drugs: saline as a solute can dissolve other drugs, such as antibiotics, other injectable drugs and so on. For example, nowadays all the infusion treatment, the vast majority of them are dissolved and infused through saline. 2. Maintain fluid balance: saline is mainly composed of sodium chloride, i.e. sodium and chloride ions, which is mainly used in drugs, such as oral rehydration solution, etc., for replenishing body fluids and maintaining electrolyte balance. 3. Cleaning wounds: saline as a topical rinse agent, such as the emergence of trauma, the wound through the use of saline for rinsing, play a role in cleaning sterilization, antibacterial. Saline is recommended to be used in accordance with the instructions, or as prescribed by the doctor.