Which IV fluid is most commonly used?

Normal saline is commonly identified as the most frequently used IV fluid because it is widely available and has numerous applications in hospitals, clinics, emergency care, and medication preparation. It contains 0.9% sodium chloride in sterile water and is classified as an isotonic crystalloid solution.

Normal saline may be used for extracellular fluid replacement, compatible medication dilution, line flushing, and selected cases of sodium or chloride depletion. However, it is not automatically the best fluid for every patient. Large volumes can contribute to a high chloride load and may affect acid-base balance, particularly in critically ill patients or individuals with impaired kidney function.

Lactated Ringer’s, also known as Hartmann’s solution in many markets, is another common isotonic crystalloid. It contains sodium, chloride, potassium, calcium, and a buffer precursor. Its more balanced electrolyte composition makes it suitable for many perioperative, trauma, burn, and resuscitation settings. Other frequently used solutions include dextrose 5% in water, half-normal saline, and combined dextrose-saline formulations.

Fluid selection depends on the patient’s volume status, electrolyte profile, acid-base balance, kidney and cardiac function, blood glucose, medications, and treatment objective. Clinicians must also consider compatibility because calcium-containing solutions may not be appropriate with certain drugs or blood products. Consequently, normal saline is among the most commonly stocked fluids, but clinical protocols increasingly distinguish between saline and balanced crystalloids according to patient need.