Stay Hydrated This Summer

Summer heat can put you at risk of dehydration. Dehydration happens when you lose more fluids than you take in, and your body does not have enough fluids to work properly. Learn more about the signs of dehydration and how to prevent it this summer.

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Summary

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

Diarrhea
Vomiting
Sweating too much
Urinating too much, which can happen because of certain medicines and illnesses
Fever
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
Dizziness

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
Irritability
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

Confusion
Fainting
Lack of urination
Rapid heartbeat
Rapid breathing
Shock

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