Effect
First, the isotonic saline solution accumulates in the interstitium (space between the tissues). About 2/3 of the extracellular space (space outside the cells) is determined by the interstitium. Only little of the volume supplied remains intravascular (located in the blood), which means that it has a very short hemodynamic effect (flowing in the blood).
Side effects and risks
There are very few known side effects and risks of isotonic saline solution. It is safe for pregnant women and children. Interactions with other drugs are not known.
If there is a tendency to water retention, it is not recommended to use isotonic saline solution as an infusion. With caution, saline solution should also be used in cases of kidney dysfunction (see Kidney insufficiency), high blood pressure, heart dysfunction (see Diseases of the heart) or water retention in the lungs. If isotonic saline solution is given excessively or too quickly, hypernatremia (too much sodium in the blood) and hyperchloremia (too much chlorine in the blood) may occur.
Large amounts of infusion solution can lead to hyperhydration (too much water in the body). Hyperhydration is an absolute contraindication.
