Dehydration occurs when you lose more fluid than you take in and your body doesn't have enough water and other fluids to carry out its normal functions. If lost fluid remains unreplenished, you may suffer serious consequences.
Common causes of dehydration include intense bouts of diarrhea, vomiting, fever or excessive sweating. Inadequate intake of water during hot weather or exercise also may deplete your body's water stores. Anyone may become dehydrated, but young children, older adults and people with chronic illnesses are most at risk. Mild dehydration can cause symptoms such as weakness, dizziness and fatigue. Severe dehydration is a life-threatening medical emergency.
You can usually reverse mild to moderate dehydration by increasing your intake of fluids, but severe cases need immediate medical treatment. The safest approach is not to become dehydrated in the first place. You can do that by monitoring your fluid loss during hot weather, illness or exercise, and drinking enough liquids to replace what you lose.
Causes
Your body may lose too much fluids from:
• Vomiting or diarrhea
• Excessive urine output, such as with uncontrolled diabetes or diuretic use
• Excessive sweating (for example, from exercise)
• Fever
You might not drink enough fluids because of:
• Nausea
• Loss of appetite due to illness
• Sore throat or mouth sores
Dehydration in sick children is often a combination of both -- refusing to eat or drink anything while also losing fluid from vomiting, diarrhea, or fever.
Symptoms
The body's initial responses to dehydration are:
1. Thirst to increase water intake along with
2. Decreased urine output to try to conserve water. The urine will become concentrated and more yellow in color.
As the level of water loss increases, more symptoms can become apparent. The following are further signs and symptoms of dehydration:
• Dry mouth
• The eyes stop making tears
• Sweating may stop
• Muscle cramps
• Nausea and vomiting
• Lightheadedness (especially when standing).
The body tries to maintain cardiac output (the amount of blood that is pumped by the heart to the body); and if the amount of fluid in the intravascular space is decreased, the body has to increase the heart rate, which causes blood vessels to constrict to maintain blood pressure. This coping mechanism begins to fail as the level of dehydration increases.
With severe dehydration, confusion and weakness will occur as the brain and other body organs receive less blood. Finally, coma and organ failure will occur if the dehydration remains untreated.
Treatment
Drinking fluids is usually sufficient for mild dehydration. It is better to have frequent, small amounts of fluid (using a teaspoon or syringe for an infant or child) rather than trying to force large amounts of fluid at one time. Drinking too much fluid at once can bring on more vomiting.
Electrolyte solutions or freezer pops are especially effective. These are available at pharmacies. Sport drinks contain a lot of sugar and can cause or worsen diarrhea. In infants and children, avoid using water as the primary replacement fluid.
Intravenous fluids and hospitalization may be necessary for moderate to severe dehydration. The doctor will try to identify and then treat the cause of the dehydration.
Most cases of stomach viruses (also called viral gastroenteritis) tend to resolve on their own after a few days.
