What is dehydration?
Dehydration happens when your body loses more fluids than it replaces. When fluid levels drop too low, the body may also lose important minerals called electrolytes. Mild dehydration can cause discomfort, while severe dehydration can become a medical emergency.
Common causes of dehydration include:
- Vomiting or diarrhea
- Fever
- Heavy sweating
- Intense exercise
- Spending time in hot temperatures
- Not drinking enough fluids
- Certain medicines that increase urination
Older adults, young children, and people with chronic health conditions may have a higher risk of dehydration.
Symptoms
Dehydration can develop quickly, especially during illness, exercise, or hot weather. Symptoms may range from mild to severe depending on how much fluid the body has lost.
Common symptoms include:
- Feeling very thirsty
- Dry mouth or dry skin
- Dark yellow urine
- Urinating less often
- Headache
- Tiredness or weakness
- Dizziness or lightheadedness
- Muscle cramps
- Fast heartbeat
Severe dehydration may also cause:
- Confusion
- Fainting
- Rapid breathing
- Extreme weakness
How is it diagnosed?
Healthcare providers diagnose dehydration by reviewing symptoms, recent illness, activity level, and fluid intake. A physical exam helps check for signs such as low blood pressure, dry skin, or rapid heart rate.
Blood and urine tests may also be used to measure electrolyte levels and determine how severe the dehydration is.
How is it treated?
Treatment depends on the amount of fluid loss and the cause of dehydration.
Mild cases are often treated by drinking water or fluids that contain electrolytes. Oral rehydration drinks may help restore both fluids and minerals lost through sweating, vomiting, or diarrhea.
Moderate or severe dehydration may require intravenous (IV) fluids in a hospital or urgent care setting. Providers also treat the underlying cause, such as infection, fever, or stomach illness.
Most people recover quickly once fluids and electrolytes are replaced.
