Lactated Ringer’s solution is an intravenous fluid that doctors use to treat dehydration and restore fluid balance in the body. The solution consists primarily of water and electrolytes.
Other names for lactated Ringer’s solution include Ringer’s lactate solution and sodium lactate solution.
This article describes lactated Ringer’s solution in more detail, including how it works and how it compares with saline. It also explains the potential side effects and risks of lactated Ringer’s solution.
Lactated Ringer’s solution, or simply “lactated Ringer’s” (LR), is one of two intravenous (IV) fluids that doctors commonly use to restore hydration and fluid balance in the body. The other solution is saline.
LR is an isotonic fluid, meaning that it has the same osmotic pressure, or weight, as blood. Osmotic pressure is a measure that takes into account solutes, such as electrolytes, and solvents, such as water. About 1 liter of LR is sufficient to restore blood volume to its normal levels.
LR also provides the body with sodium lactate, which it can use as fuel in conditions of reduced or restricted blood flow and oxygen.
As an alkalizing agent, LR also helps reduce the levels of acidity within the body. Therefore, doctors may use the solution to treat high acid levels resulting from sepsis or other conditions.
A doctor may administer LR alone or alongside other medications or nutrients.
LR and saline differ in terms of their chemical content and their overall effects on the body. LR does not last as long in the body, so it is less likely to cause fluid overload, known as hypervolemia. In addition, it is formulated with sodium lactate to promote the metabolization of bicarbonate, thereby lowering acidity in the body.
A 2020 study involving people who had undergone colorectal or orthopedic surgery investigated the difference in outcomes between people receiving LR and those getting the equivalent volume of saline solution. The researchers found no statistically significant difference between the two groups for any of the variables that they measured. These included:
Although both LR and saline are equally effective in most clinical settings, research suggests that LR might be more effective for trauma patients experiencing burns or excessive blood loss.
Medical professionals may administer LR in a hospital setting to treat dehydration and restore fluid balance in the body. A doctor will sometimes select LR over traditional saline because it does not remain in the body for as long and is less likely to result in hypervolemia.
Doctors will not typically administer LR for people undergoing blood transfusions, as it can interact with certain blood medications to increase the risk of clotting. If a doctor does decide to administer the two treatments, they will administer each one through a separate IV line.
LR is an IV medication, meaning that a doctor or trained nurse will administer it into a vein. The fluid will pass from an external IV bag, through an IV line, and into the bloodstream.
IV fluid regulation refers to the monitoring and control of how much fluid passes from the bag into the bloodstream. Medical professionals may administer LR in one of two ways: manually or via an electric pump.
With the manual technique, a healthcare professional adjusts the pressure of the clamp on the IV tube to reduce or facilitate the flow rate. They may also count the number of drops per minute to ensure an accurate and safe flow.
With the electric pump method, a healthcare professional programs an electric pump to deliver the correct dosage of LR automatically. According to the Food and Drug Administration (FDA), many of the reported problems with fluid infusion are due to electric pump use. For instance, these devices can be faulty, or software or electrical issues can occur.
Side effects due to LR are rare, and those that do occur are more commonly the result of an intolerance or allergic reaction to the solution. Some rare side effects, which occur at the injection site, include:
Overall, LR has few associated risks. However, any type of IV fluid administration may lead to complications for people with one or more of the following conditions:
The above health conditions reduce the body’s ability to remove excess fluid. IV fluid administration further increases the risk of hypervolemia and associated swelling and edema. If a person with any of these conditions requires LR or saline, a medical professional will monitor them closely for signs of hypervolemia.
In previous years, some medical professionals expressed concern over using LR during blood transfusions. The reason for this concern was that some anticoagulant, or blood-thinning, medications contain citrate, while LR contains high levels of calcium. Mixing citrate with calcium can cause blood clotting and obstruct an IV line.
However, a person can receive anticoagulant medications and LR at the same time, as long as a medical professional delivers each treatment through a separate IV line.
Lactated Ringer’s is one of two common IV solutions that a doctor may administer to restore the balance of fluids and electrolytes in the body. The other IV solution is saline. The two solutions differ in their chemical makeup and their effects on the body. Unlike saline, LR has an alkalizing effect on the body. It also remains inside the body for a shorter period.
LR is safe for most people. However, it can cause allergic reactions, such as discoloration, itchiness, and swelling at the injection site.
People with certain medical conditions — such as congestive heart failure, liver failure, or chronic kidney disease — have an increased risk of swelling when receiving any type of IV fluid. Anyone who has any of these conditions will receive close monitoring to ensure that their fluid levels remain within the normal range.
Last medically reviewed on July 26, 2021