It’s a hot, summer day, the sun is shining and you can’t stop sweating. It is on days like this when it is important to stay hydrated because dehydration can set in quickly when your body doesn’t have enough fluid.

“Think of what a house plant looks like that doesn’t have enough water,” said Leon Veldhuizen, M.D., a Marshfield Clinic Health System family medicine physician. “It starts to wilt and shrink up. It’s the same with our bodies. If we don’t have enough fluid, things won’t work properly.”

How dehydration happens

We mainly lose water through perspiration, urination and excreting bowels. When it’s warmer, you lose more fluid through sweat, making it easier to become dehydrated.

Elderly people and the very young are most affected. Illness or fever, vomiting and diarrhea (from infection or from a bowel disorder), and increased urination from uncontrolled diabetes or from certain medicines like water-pills, also can cause dehydration.

Young children can become fussier, sweat more, stop crying, become lethargic and have a decreased number of wet diapers or dark colored urine.

“Among the first symptoms to show up are a dry mouth, less urination, dark-colored urine, fatigue, dizziness, dry skin, headache, muscle cramps or feeling thirsty,” said Lexie Schwartz, RN and Emergency Department Manager at Marshfield Medical Center-Rice Lake. “In babies and children, dehydration can occur quicker due to the smaller body size. Watch for sunken eyes, irritability, and unusual fatigue, crying with no tears, a dry mouth or tongue and less wet diapers than usual.”

More severe symptoms include confusion, fainting, no urine production, rapid heartbeat and breathing, a high temperature, seizures, hot, dry skin, hallucinations and signs of shock.

“If early, non-severe symptoms of dehydration are noticed, treatment is as simple as drinking fluids,” Schwartz said. “In more severe cases, IV fluids in a hospital may be needed and medical attention should be sought.”

Prepare to stay hydrated

Water is the most helpful drink to counter dehydration. In some situations, sports drinks also may be used, as they contain electrolytes and vitamins in addition to fluids to help replenish what was lost. Oral rehydration solutions may help replace fluids and electrolytes for children, without the added sugar that is found in some sports drinks.

“Someone who is dehydrated should avoid drinks with alcohol or caffeine, as well as situations that will cause excess sweating, like going in a sauna, intense exercise and being in extremely hot weather,” Schwartz said. “It’s best to stay in a comfortable temperature environment, rest and drink fluids if mild dehydration occurs.”

Dr. Veldhuizen says the most important thing is to prepare before going into a warm or hot environment so you don’t become dehydrated.

Get enough fluids into your body daily

A good rule of thumb for adults is drinking 12 eight-ounce glasses of fluids daily, but to replenish fluids lost if you live a more active lifestyle.

“Carry a water bottle with you during the day and keep it filled. Adding flavor to the water can make it more fun to drink,” Schwartz said. “Getting enough fluids doesn’t always mean only drinking water. Adding foods high in water content to your diet, such as fruits and vegetables, help provide hydration.”

Learn what dehydration feels like

This graphic explains what happens when you become dehydrated and what you can do to stay hydrated.

For immediate care, visit Marshfield Clinic Health System.

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