Water intoxication: Is it possible to die from drinking too much water?

Everyone is aware of the fact that water is absolutely essential for good health. All major systems of the body depend on water to function properly. Drinking adequate amount of water is not only beneficial, but also pertinent for the healthy functioning of our body. Drinking enough water is vital for regulating body temperature, preventing constipation, flushing out waste products, keeping the organs healthy, and so much more. However, whenever it comes to taking something inside the body, it is always better to remember that excess of anything is bad. Though the body requires an adequate amount of water to function properly, over consumption of water can cause something known as water intoxication. This is a condition that can cause a plethora of discomfort for an individual and in extreme cases can also prove to be fatal.

What is water intoxication?

Water intoxication is a disruption of brain function caused by drinking too much water. It is also known as water poisoning or over-hydration. This causes dilution of electrolytes in the body, especially sodium in the blood. If sodium levels fall below 135 millimoles per liter, the condition is known as hyponatremia.

Sodium helps maintain the balance of fluids inside and outside of cells. When sodium levels drop due to excessive water consumption, fluids travel from the outside to the inside of cells, causing them to swell.

When this happens to brain cells, it can be dangerous and even life threatening.

According to some recent studies, popular actor and martial artist Bruce Lee died at a very young age due to cerebral edema. This could have been caused by over-hydration.

Hyponatremia, a word cobbled together from Latin and Greek roots, translates as “insufficient salt in the blood.” Quantitatively speaking, it means having a blood sodium concentration below 135 millimoles per liter, or approximately 0.4 ounces per gallon, the normal concentration lying somewhere between 135 and 145 millimoles per liter. Severe cases of hyponatremia can lead to water intoxication, an illness whose symptoms include headache, fatigue, nausea, vomiting, frequent urination and mental disorientation.

In humans the kidneys control the amount of water, salts and other solutes leaving the body by sieving blood through their millions of twisted tubules. When a person drinks too much water in a short period of time, the kidneys cannot flush it out fast enough and the blood becomes waterlogged. Drawn to regions where the concentration of salt and other dissolved substances is higher, excess water leaves the blood and ultimately enters the cells, which swell like balloons to accommodate it.

Most cells have room to stretch because they are embedded in flexible tissues such as fat and muscle, but this is not the case for neurons. Brain cells are tightly packaged inside a rigid boney cage, the skull, and they have to share this space with blood and cerebrospinal fluid. Thus, brain edema, or swelling, can be disastrous.

What are the symptoms of water intoxication?

Symptoms of water intoxication generally appear if a person consume over three to four liters of water in just a few hours. Some common symptoms may include the following:

• head pain
• cramping, spasms, or weakness in your muscles
• nausea or vomiting
• drowsiness and fatigue

Severe cases of water intoxication can produce more serious symptoms, such as:

• drowsiness
• muscle weakness or cramping
• increased blood pressure
• double vision
• confusion
• inability to identify sensory information
• difficulty breathing

In severe cases, water intoxication might result in fits or seizures, and even loss of consciousness. If treatment is not available on time, water intoxication can prove to be fatal as well.

Death by over-hydration is rare but it is certainly not impossible. There have been documented cases of death due to water poisoning as well.

What can cause water intoxication?

Water intoxication is rare, and it is very difficult to consume too much water by accident. However, it can happen — there have been numerous medical reports of death due to excessive water intake.

Water intoxication most commonly affects people participating in sporting events or endurance training, or people who have various mental health conditions.

Sporting events

Water intoxication is particularly common among endurance athletes. It can happen if a person drinks a lot of water without correctly accounting for electrolyte losses.

For this reason, hyponatremia often occurs during major sporting events.

Instances of water intoxication at these events have resulted in death. One case involved a runner who had collapsed after a marathon.

Because he was improperly rehydrated, his sodium levels fell below 130 mmol/l. The runner then developed water on the brain, known as hydrocephalus, and a hernia in his brain stem, which caused his death.

Military training

One medical report described 17 soldiers who developed hyponatremia after drinking too much water during training. Their blood sodium levels were 115–130 mmol/l, while the normal range is 135–145 mmol/l.

According to another report, three soldiers died due to hyponatremia and cerebral edema. These deaths were associated with drinking more than 5 liters of water in just a few hours.

The symptoms of hyponatremia can be misinterpreted as those of dehydration. According to one report, a soldier who received an incorrect diagnosis of dehydration and heat stroke died from water intoxication as a result of rehydration efforts.

Mental health conditions

Compulsive water drinking, also called psychogenic polydipsia, can be a symptom of various mental health conditions.

It is most common among people with schizophrenia, but it can also arise in people with affective disorders, psychosis, and personality disorders.

How much water is too much?

There isn’t a set amount of water that always causes life-threatening water poisoning. Instead, it’s best to think in terms of the amount of water that someone drinks per hour. Someone’s age, gender, and overall health can also play a role.

The kidneys of a healthy adult can flush out 20 to 28 L of water each day, but they can only get rid of about 1 L each hour. This makes it hard for your kidneys to keep up when you drink more than 1 L per hour.

The kidneys of older adults and children tend to be less efficient, so the amount of water that they can safely drink per hour might be a bit lower.

Treatment for water intoxication

Treatment for water intoxication focuses on preventing complications and worsening of the condition, and relieving symptoms. It will also depend on the severity of the condition, the symptoms present, and the stage of progression.

Treatment options for water intoxication may include:

• hypertonic saline
• close monitoring of symptoms and sodium levels
• medications such as vasopressin antagonists and mannitol
• limitation of water intake
• behavioral therapy if the cause is behavioral

If your condition occurs as a result of a certain medication, your doctor may recommend discontinuing its use. However, it is important to continue using any prescribed medications until you receive advice from your doctor.