The human body normally contains a lot of water. It helps keep your body healthy and working well.
Dehydration is when you don’t have enough water in your body. Mild dehydration can cause problems with blood pressure, heart rate, and body temperature. Severe dehydration can also cause weakness or confusion. In extreme cases, it can lead to brain damage and even death.
Everyone loses body water daily through sweat, tears, breathing, urine and stool. This water is replaced by drinking fluids and eating foods that contain water.
Dehydration can have many causes. You may have lost water from sweating, diarrhea or vomiting. Or you may be sweating from exercise or hot weather.
Loss of water often leads to an imbalance of electrolytes in the body. Electrolytes are minerals and salts that the body needs to function. They include sodium, potassium, magnesium and calcium.
“Staying well hydrated decreases symptoms of lightheadedness and headaches, improves constipation, decreases muscle cramping, and decreases risk of kidney problems such as stones and urinary tract infections,” Dr. Canham said.
In the heat of summer, or during an illness, here’s some information to keep in mind about dehydration, including symptoms that should prompt you to seek medical attention.
What causes dehydration?
Dehydration can be caused by:
- Sweating from hot weather, exercise, sauna use
- Some medicines that cause extra urination, such as diuretics
Who is at risk for it?
You are more at risk if you:
- Have diarrhea
- Have vomiting
- Are in hot weather
- Have been sweating a lot from exercise
- Are an adult age 60 or older
What are the symptoms of dehydration?
Symptoms can occur a bit differently in each person. They can include:
- Muscle cramps
- Dry mouth
- Less urine
- Urine that’s more yellow or even light brown in color
- Dry skin or tongue
- Fast heart rate and breathing
The symptoms of dehydration can look like other health conditions. See your health care provider for a diagnosis.
How is dehydration diagnosed?
Your health care provider will ask about your symptoms and health history. The provider also may ask about recent illness or activity. They will give you a physical exam. Your blood pressure, temperature and heart rate will be checked. You may have blood or urine tests.
How is it treated?
Treatment will depend on your symptoms, your age and your general health. It also will depend on how severe the condition is. You also may be treated for diarrhea, vomiting or a high fever if illness caused your dehydration.
For moderate to severe dehydration, you might need IV (intravenous) fluids. Severe dehydration is a medical emergency. It needs to be treated right away with IV fluids in a hospital.
For mild dehydration, you can drink fluids. You may need to restore not just water, but also electrolytes such as sodium and potassium. Sports drinks can replace water and electrolytes. You can also drink water, fruit juices, tea and soda.
Don’t have drinks with caffeine. These include some energy drinks, teas, sodas and coffee drinks. Don’t drink alcohol. Caffeine and alcohol may cause your body to lose more water.
Talk with your health care providers about the risks, benefits and possible side effects of all treatments.
What are possible complications of dehydration?
Severe dehydration that is not treated can cause kidney damage, brain damage and death.
What can I do to prevent it?
Drink 12 (8-ounce) glasses of fluid every day. Drink more if you are in hot weather or exercising. Drinks may include:
- Fruit juices
- Sports drinks (be careful of the sugar in these drinks, especially if you have diabetes)
- Other drinks that have electrolytes
- Soda with no caffeine
- Tea with no caffeine
- Coffee with no caffeine
“An obvious but often forgotten recommendation is to make sure you always have fluids with you or access to fluids. Carry a water bottle around for yourself and for your family members,” Dr. Canham said. “Also, set goals throughout the day of certain number of fills of the water bottle by a certain time of day depending on how big your water bottle is.”
If you have been diagnosed with a kidney disease, ask your health care provider how much and what types of fluids you should drink to prevent dehydration. When you have kidney disease, fluid can build up in the body. This can be dangerous to your health.
When should I call my health care provider?
Call the health care provider for dehydration if you have:
- Diarrhea more than 5 times a day
- Continued vomiting
- Blood (red or black color) or mucus in diarrhea
- Blood in vomit
- Belly pain
- Swollen belly
- Fever of 100.4°F or higher, or as directed by your health care provider
Call 911 or go to the emergency room if you have:
- Dizziness or fainting
- Drowsiness or confusion