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Symptoms of dehydration: infant or young child - Children—babies and toddlers—are particularly vulnerable to dehydration. But how do you know if a baby is dehydrated? There are several signs to look out for, including a decrease or absence of tears.

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Symptoms of dehydration: infant or young child - No wet diapers for three hours or more? That's a clear sign that your little one is dehydrated.

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Symptoms of dehydration: infant or young child - Another tell-tale sign of a dehydrated baby is the sunken appearance of the fontanel (or soft spot on head).

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Symptoms of dehydration: infant or young child - Infants and young children can also display a sallow, sunken look in their eyes if they've not drunk enough liquids.

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Symptoms of dehydration: infant or young child - If your youngster has a dry mouth or tongue, then it's time to get them drinking water or other fluids.

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Symptoms of dehydration: adult - Adults too can fall victim to dehydration. Extreme thirst is an obvious sign that you're not drinking enough fluids.

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Symptoms of dehydration: adult - Feeling more tired than usual? Mild or moderate dehydration can cause sleepiness and an overall sensation of lethargy.

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Symptoms of dehydration: adult - The onset of dizziness is another indicator of dehydration. 

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Symptoms of dehydration: adult - Diminished fluid intake can also promote headache and ultimately lead to a confused state. Dizziness or light-headedness that does not allow the person to stand or walk normally indicates a serious progression of dehydration.

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Symptoms of dehydration: adult - Less frequent urination and urine that is low in volume or more yellowish in color is a sign or symptom of dehydration.

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Symptoms of dehydration: adult - In fact the darker your urine is, the less your fluid intake—and the more serious your dehydration! When it's highly concentrated, your urine can vary from dark yellow to orange. The solution is to drink more fluids, especially water.

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When to seek medical advice - Abnormal bowel movement is indicative of a number of problems, including dehydration. Seek immediate medical advice if this is the case.

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When to seek medical advice - Acute diarrhea can cause a tremendous loss of water and electrolytes in an alarmingly short amount of time. If you suffer from the condition for more than 24 hours, it's time to call the doctor.

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When to seek medical advice - If you have vomiting along with diarrhea, you'll lose even more fluids and minerals. Again, if the illness persists, make an appointment with your doctor as soon as possible.

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Causes of dehydration - Excessive sweating is a common cause of dehydration. You lose water when you sweat, so if you indulge in vigorous exercise or activity and don't replace fluids as you progress, you can become quickly dehydrated. And remember, a hot, humid climate increases the amount you sweat and the volume of fluid you lose.

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Causes of dehydration - Bear in mind that increased urination can also precipitate dehydration. The urge to go can be exacerbated by the use of certain medications including diuretics and some blood pressure medications. Beware, though. Increased urination can also be indicative of undiagnosed or uncontrolled diabetes.

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Causes of dehydration - As a rule of thumb, the higher your fever, the more dehydrated you may become. The problem is exacerbated if you have a fever in addition to diarrhea and vomiting. You also run the risk of sweating excessively.

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Dehydration: risk factors - People with diabetes have an increased risk of dehydration as high blood glucose levels lead to decreased hydration in the body. Water is even pulled from your tissues to help get rid of the extra sugar! Kidney disease also increases your risk, as do medications that increase urination.

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Dehydration: risk factors - Working or exercising outside in a hot or humid climate poses considerable risk to anyone who doesn't keep themselves hydrated. Sweat can't evaporate and cool you as efficiently as it normally does, and this can lead to an increased body temperature and the need for more fluids.

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Dehydration: risk factors - Young children and older people are especially vulnerable to dehydration, as the loss of electrolytes occurs more rapidly in these two groups of people. Remember, babies can't tell you when they are thirsty, nor can they get a drink for themselves.

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Dehydration: risk factors - Signs of dehydration in seniors may include rapid heart rate, low blood pressure, and difficulty walking—itself a problem in that it can limit their ability to obtain water for themselves. The body's fluid reserve decreases as you age and with it your ability to conserve water. In addition, your thirst sensation becomes less acute.

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Complications of dehydration - Dehydration is often accompanied by an imbalance of sodium, potassium, chloride, and other electrolytes. Electrolytes help carry electrical signals from cell to cell. An imbalance can scramble these electrical messages, which can lead to involuntary muscle contractions and sometimes to a loss of consciousness.

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Complications of dehydration - Heat exhaustion can be brought on by undertaking vigorous physical activities in hot and humid weather. Even perspiring heavily can induce mild heat cramps. But it's potentially life-threatening heatstroke that raises a red flag. Always notify emergency services immediately if heat stroke is suspected.

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Complications of dehydration - Another serious and potentially life-threatening complication of dehydration is low blood volume shock (hypovolemic shock). It happens when a sudden and significant loss of blood or body fluids drops your blood volume, which in turn causes a drop in blood pressure and a drop in the amount of oxygen in your body.

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Complications of dehydration - Your kidneys are not immune to the effects of dehydration. Indeed, prolonged or repeated bouts of dehydration can cause kidney stones, and even kidney failure. Becoming dehydrated can also lead to urinary tract infections.

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Dehydration: prevention - It's important to drink plenty of fluids even during minor illnesses, for example influenza and bronchitis. Older people especially should remain hydrated. Generally speaking, when you're not feeling well, drink lots of fluids.

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Dehydration: prevention - As a reminder, if your child is vomiting or has diarrhea start giving water or an oral rehydration solution immediately. Children should take small sips every few moments.

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Dehydration: prevention - Drinking additional water in hot or humid weather is an obvious solution to help beat the heat. What's not so obvious perhaps is to drink extra water in cold weather to combat moisture loss from dry air, particularly at higher altitudes.

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Dehydration: prevention -

Include water in your daily exercise regime. In fact, start hydrating the day before strenuous exercise. And remember to replenish fluids at regular intervals during your workout.

See also: How to identify the warning signs of a stroke.

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