What is a common isotonic IV solution?

A common isotonic IV solution is Normal saline. Isotonic solutions have an osmolarity similar to that of blood plasma, which helps to maintain balanced fluid levels in the body without causing cells to shrink or swell. Normal saline, a sterile solution of sodium chloride in water, is widely used for hydration, electrolyte replenishment, and as a diluent for medications.

While Lactated Ringer's solution is also isotonic and contains a blend of electrolytes, it is more specifically designed for fluid resuscitation and is often used in surgical patients or those with burns. Dextrose 5% in water is considered hypotonic when administered and can lead to cellular swelling; its primary use is for providing calories. Hypertonic saline, on the other hand, increases osmolarity and draws water out of cells, which can lead to dehydration of cells, making it unsuitable as an isotonic solution. Thus, Normal saline is recognized as the quintessential isotonic IV solution used in various clinical settings.