Sodium Chloride: Medical Uses, Side Effects, and More

The chemical formula for salt is NaCl

Medically reviewed by Suzanne Fisher, RD

Sodium chloride (NaCl) is a key compound also known as salt. It consists of sodium and chloride atoms. When dissolved in body fluids or water, these minerals have an electric charge, becoming sodium ions and chloride ions. In ion form, they are also known as electrolytes.

Sodium chloride is an important nutrient. When your sodium chloride level is too low, it must be increased to maintain normal body function. When it is too high, you should reduce it to prevent heart disease and other health problems.

Sodium chloride is also used in medical treatments to prevent symptoms of dehydration or overhydration. It can replace electrolytes lost as a result of disease, sweating, or other issues.

This article describes how sodium chloride works in your body and the ways it is used in treatments. It also explains when you may have to increase or decrease your salt intake.

<p>FG Trade / Getty Images</p>

FG Trade / Getty Images

Sodium Chloride in the Human Body

Your body does not produce sodium chloride. You obtain it from foods with naturally occurring salt, such as milk, meat, and shellfish, or foods with salt added as a seasoning or preservative. Extra sodium chloride is eliminated in perspiration and urine.

Each component of salt provides essential support for overall well-being. Sodium provides the following benefits:

Chloride makes key contributions to normal body function in the following ways:

  • Regulates the amount of fluid and nutrients going in and out of cells

  • Maintains normal pH levels (acid/base balance)

  • Promotes stomach acid needed for digestion

  • Facilitates the flow of oxygen and carbon dioxide within your cells

  • Stimulates the action of nerve and muscle cells

Though most Americans consume about 3,400 milligrams (mg) of sodium daily, the American Heart Association recommends a daily sodium limit of 2,300 mg, with an ideal limit of 1,500 mg.

Americans typically consume too much sodium because it is commonly added to so many foods, especially processed foods such as bread, pizza, soups, and snacks like potato chips.

Sodium vs. Table Salt

The words "sodium" and "table salt" are often used to mean the same thing. However, they don't. Sodium is just one component of table salt. Table salt is a combination of sodium and chloride. It occurs naturally or as an additive in some foods.

Sodium Chloride Medical Uses

Sodium chloride is mixed with water to create a saline solution, which is used in different medical applications.


Sodium chloride injections are used to treat dehydration and replace electrolytes and water. The solutions can be mixed with sugar if necessary. Though injections are available in syringes, they are typically administered as intravenous (IV) drips because of the amount of liquid required to achieve results.

Purpose: Replace electrolytes and water to counter dehydration

Side effects:

  • Redness, irritation, or infection at the injection site

  • Fever

  • Venous thrombosis (blood clot in a vein) or phlebitis (vein inflammation) extending from the injection site

  • Extravasation (a skin reaction caused by leakage of a liquid from a blood vessel or IV tube onto the surrounding skin)

  • Hypervolemia (a lack of circulating fluids)

  • Anaphylaxis (a severe and life-threatening allergic reaction)

Oral Tablets

Sodium chloride oral tablets are used as electrolyte replenishers for salt lost as a result of fever, hot weather, or vigorous exercise.

The tablets can also supplement salt levels in people with cystic fibrosis for whom dehydration poses a severe problem. In people with cystic fibrosis, dehydration can lead to thicker lung mucus, which increases difficulty in expelling secretions and causes potential gastrointestinal blockages.


Side effects:

  • Swelling of the hands, legs, and feet

  • Stomach pain

  • Vomiting

  • Allergic reaction characterized by the following symptoms: difficulty breathing, skin rash, swelling, itching, severe dizziness

Saline Flush Injections

Saline flush injections flush an IV or catheter after a medication is administered.


  • Push residual medication or fluid through an IV or catheter line and into your vein

  • Prevent IV lines or catheters from becoming blocked

Side effects:

  • Air embolism (air bubble in blood vessel) with stroke, chest pain, and dyspnea (shortness of breath)

  • Arrhythmia (irregular heart rhythm)

  • Low blood pressure

  • Infection, venous thrombosis, or phlebitis extending from the injection site

  • Fluid overload

Nasal Irrigation or Nasal Drops

Saline nasal irrigation sprays or nose drops to relieve congestion and dry nasal tissue can be purchased without a prescription or made at home.


Side effects: Stinging or dryness in your nose, usually from preservatives

Cleaning Wounds

Saline is the preferred cleanser for most wounds because it is always considered safe. Research indicates it is preferable to soap and water.


  • Cleanse open sounds

  • Prevent infection

Side effects:

  • Mild irritation

  • Infection at the site of the wound

Eye Drops

Sodium chloride eye drops are an ophthalmic (eye) solution that works by replacing the salt and electrolyte levels in your eye area. The eye drops draw fluid out of your cornea to reduce redness, swelling, tearing, and irritation caused by swelling.


  • Short-term fluid replacement after trauma or dehydration

  • Treatment of symptoms of dry eyes

  • Relief from pain and redness

  • Temporary relief of corneal edema (swelling or blurriness after injury, infection, eye surgery, or inflammation)

Side effects:

  • Burning sensation in the treated eye(s)

  • Temporary blurring of vision in the treated eye(s)

  • Worsening sensations of burning or blurry vision that do not improve

Sodium Chloride Inhalation

Sodium chloride inhalation is used with a nebulizer, a small machine that turns liquid medicine into a mist that is inhaled through a mask or mouthpiece. The medicine passes from your mouth to your lungs. It is often used to administer asthma medication or treatments for chronic lung diseases.

Purpose: To dilute asthma medicine for nebulization

Side effects: allergic reactions characterized by the following symptoms:

  • Itching or hives

  • Swelling in your face or hands

  • Difficult breathing

  • Swelling or tingling in your mouth or throat

  • Chest tightness

Types of Sodium Chloride

Sodium chloride for medical treatment comes in many forms and strengths, based on its use. Formulations come in numerous brand names as well as generics.

Sodium chloride injections:

  • BD Posiflush Normal Saline (0.45% sodium chloride injection)

  • BD Posiflush Normal Saline (0.9% sodium chloride injection)

  • Hypertonic saline (3% sodium chloride injection)

  • Hypertonic saline (5% sodium chloride injection)

Sodium chloride concentrate for dilution before IV or nebulizer administration:

  • Sodium Chloride Intravenous Injection Solution Concentrate (14.6% sodium chloride)

  • Sodium Chloride Intravenous Injection Solution Concentrate (23.4% sodium chloride)

Sodium chloride oral:

  • CitraGen (1 gram sodium chloride tablet)

  • Safecor Sodium Chloride oral solution (24.3% sodium chloride concentrated oral solution)

Sodium chloride inhalation:

  • Nebusal (3% sodium chloride)

  • Hypersal (3.5% sodium chloride)

  • Nebusal (6% sodium chloride)

  • Hypersal (7% sodium chloride)

  • Hypersal, Nebusal, Pulmosal (10% sodium chloride)

Sodium chloride wound cleaning:

  • SafeWash, Saline Wound Flush (0.9% sodium chloride)

Sodium chloride nasal spray:

  • Ocean, Altamist, Breathe Free Saline, and others (0.65% sodium chloride)

  • Rhinaris, Mupirocin, and others (0.2% sodium chloride)

Sodium chloride ophthalmic:

  • Hyper-NC (5% sodium chloride)

  • Muro-128 (2% sodium chloride)

When Do People Need More Sodium Chloride?

You only need a small amount of sodium chloride, about 500 milligrams daily, to help your body function normally. Though most people have too much salt in their diet, consuming inadequate amounts of salt can also cause problems.

If you develop hyponatremia (low sodium levels in your blood), you may need more sodium chloride. Hyponatremia is defined as a blood serum sodium concentration of less than 135 milliequivalents per liter (mEq/L). Inadequate sodium levels in the blood can affect blood pressure and muscle and nerve function.

Inadequate sodium levels allow extra water to move into cells, causing swelling and organ malfunction. Hyponatremia doesn't always cause symptoms unless the blood sodium level drops very low or the decline occurs very quickly.

Symptoms of hyponatremia include:

  • Nausea

  • Headache

  • Muscle weakness, cramps, or spasms (twitching)

  • Low blood pressure

  • Dizziness when standing up

  • Fatigue or low energy

  • Loss of appetite

  • Bad temper or restlessness

When sodium levels fall extremely low, the outcome can be dangerous, especially in your brain, where there is little room for swelling tissue to expand. The following severe symptoms of hyponatremia may indicate a life-threatening situation:

  • Altered mental state and severe confusion

  • Cardiac arrest (a sudden loss of consciousness, breathing, and pulse)

  • Vomiting

  • Hallucinations

  • Decreased consciousness

  • Rhabdomyolysis (life-threatening muscle breakdown)

  • Seizures

  • Coma

Hyponatremia is typically related to having too much water in your body rather than not eating enough sodium. It can be caused by a wide range of factors, including:

  • Burns on a large area of your body

  • Increased fluid loss from diarrhea or vomiting

  • Heart failure

  • Diuretic medications like water pills, which increase your urine output and the loss of sodium through urine

  • Kidney disease, which makes it hard for your kidneys to remove extra fluid from your body

  • Cirrhosis (advanced liver disease), which allows the buildup of extra fluid that dilutes your blood

  • Excessive sweating due to exercise, extreme heat, or other factors

  • Drinking too many fluids and diluting your blood, sometimes due to excessive thirst

  • Syndrome of inappropriate antidiuretic hormone secretion (SIADH), in which your body retains too much water and flushes out too much sodium in your urine

  • Certain medications that treat conditions including depression, seizures, and cancer

Learn More: How Much Sodium You Need Per Day

When Do People Need Less Sodium Chloride?

Most people in the United States consume too much sodium chloride. This can lead to hypernatremia (an abnormally high level of sodium in the blood). Hypernatremia is defined as a blood serum sodium concentration greater than 145 mEq/L.

Sodium attracts water. Too much sodium in the blood causes water to be transferred out of your cells and into your blood, diluting it. You may need less sodium chloride if you have signs of hypernatremia, which include the following:

  • Bloating

  • Swollen hands or feet

  • Increased thirst

  • Headache

  • Rise in blood pressure

Symptoms of more severe damage caused by high salt levels include the following:

  • Nausea and vomiting

  • Loss of appetite

  • Muscle weakness

  • Confusion

  • Difficulty breathing

  • Kidney damage

  • Seizures

  • Coma

You may need less salt if you have any of the following risk factors that lead to hypernatremia:

Learn More: 6 Tips for Lowering Your Salt Intake


Sodium chloride, or salt, is a compound that contains sodium and chloride. These nutrients provide support to many key body functions such as cellular health and blood pressure control.

Most people consume too much salt because it is often added to processed and prepared food to season and preserve it. Lower dietary sodium chloride can help reduce severe effects from high blood pressure, heart disease, stroke, and other severe problems.

When you can't consume the lowest healthy level of sodium chloride, you may need supplementation. This can be done with oral tablets or IV injection, based on the severity of the problem. Sodium chloride is also used in treatments for your eyes, nose, and skin.

Talk to a healthcare provider about the amount of sodium chloride that you can safely consume. Factors such as your age, chronic health problems, and overall health can affect this amount.

Read the original article on Verywell Health.