What is dehydration?
Dehydration is condition caused by the loss of too much fluid from the body. It happens when you are losing more fluids than you are taking in, and your body does not have enough fluids to work properly.
What causes dehydration?
You can become dehydrated because of
- Sweating too much
- Urinating too much, which can happen because of certain medicines and illnesses
- Not drinking enough
Who is at risk for dehydration?
Certain people have a higher risk of dehydration:
- Older adults. Some people lose their sense of thirst as they age, so they don't drink enough fluids.
- Infants and young children, who are more likely to have diarrhea or vomiting
- People with chronic illnesses that cause them to urinate or sweat more often, such as diabetes, cystic fibrosis, or kidney problems
- People who take medicines that cause them to urinate or sweat more
- People who exercise or work outdoors during hot weather
What are the symptoms of dehydration?
In adults, the symptoms of dehydration include
- Feeling very thirsty
- Dry mouth
- Urinating and sweating less than usual
- Dark-colored urine
- Dry skin
- Feeling tired
In infants and young children, the symptoms of dehydration include
- Dry mouth and tongue
- Crying without tears
- No wet diapers for 3 hours or more
- A high fever
- Being unusually sleepy or drowsy
- Eyes that look sunken
Dehydration can be mild, or it can be severe enough to be life-threatening. Get medical help right away if the symptoms also include
How is dehydration diagnosed?
To make a diagnosis, your health care provider will
- Do a physical exam
- Check your vital signs
- Ask about your symptoms
You may also have
- Blood tests to check your electrolyte levels, especially potassium and sodium. Electrolytes are minerals in your body that have an electric charge. They have many important jobs, including helping to keep a balance of fluids in your body.
- Blood tests to check your kidney function
- Urine tests to check for dehydration and its cause
What are the treatments for dehydration?
The treatment for dehydration is to replace the fluids and electrolytes that you have lost. For mild cases, you may just need to drink lots of water. If you lost electrolytes, sports drinks may help. There are also oral rehydration solutions for children. You can buy those without a prescription.
Severe cases may be treated with intravenous (IV) fluids with salt in a hospital.
Can dehydration be prevented?
The key to preventing dehydration is making sure that you get enough fluids:
- Drink enough water every day. Each person's needs can be different, so ask your health care provider how much you should be drinking each day.
- If you are exercising in the heat and losing a lot of minerals in sweat, sports drinks can be helpful
- Avoid drinks that have sugar and caffeine
- Drink extra fluids when the weather is hot or when you are sick
Treatments and Therapies
- First Aid: Dehydration (Nemours Foundation)
- ClinicalTrials.gov: Dehydration (National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: To hydrate or not to hydrate? The effect of hydration on...
- Article: Hypotheses about sub-optimal hydration in the weeks before coronavirus disease (COVID-19)...
- Article: Different Amounts of Water Supplementation Improved Cognitive Performance and Mood among...
- Dehydration -- see more articles
- Drinks to Prevent Dehydration in a Vomiting Child (American Academy of Pediatrics) Also in Spanish
- Parents' and Coaches' Guide to Dehydration and Other Heat Illnesses in Children (National Athletic Trainers' Association) - PDF Also in Spanish
- Sports Dehydration Safety Tips (Safe Kids Worldwide) - PDF
- Straight Poop on Kids and Diarrhea (Food and Drug Administration)
- What's the Big Sweat about Dehydration? (For Kids) (Nemours Foundation) Also in Spanish