Fructodex Saline Infusion serves as a preservative commonly used in cough syrups. Along with preserving the medication, it also acts as a sweetener to improve taste. By masking the bitter taste of the medicine, it helps in enhancing the overall flavor, making it more palatable for patients.

It's important to note that Fructodex Saline Infusion may have side effects such as weight gain and elevated blood glucose levels. In particular, individuals with diabetes should inform their doctor before using this medication to ensure proper monitoring and management of any potential effects on blood sugar levels.

Overall, the inclusion of Fructodex Saline Infusion in cough syrups serves a dual purpose of acting as both a preservative and a sweetening agent. However, it's crucial for users to be aware of the potential side effects associated with this ingredient, especially if they have underlying health conditions like diabetes.