Dehydration is happening when you lose or use more than fluid you take in and your body does not have enough water and other fluids to carry out its normal functions. If we do not replace the lost fluids in your body, then you will get dehydrated. Any single person can become dehydrated but this condition is very dangerous for young children and older adults. Severe diarrhea and vomiting are the most common causes of dehydration in young children . Older adults naturally have a lower volume of water in their bodies and also they might have some conditions or they take medications which is increasing their risk of dehydration. This means that even minor issues such as infections that are affecting your bladder or lungs, then it can result in dehydration in older adults . This condition can happen at any age and if you do not drink enough amounts of water during the hot weather and if you are exercising vigorously in this period, then your chances of dehydrating are increased. When you drink more fluids, then you can easily reverse mild to moderate dehydration but if you have severe dehydration, then you should seek medical help as soon as possible.
Symptoms of dehydration
When we feel thirst, then this is not always the early indicator that our body needs more water. There are many people, particularly older adults which are not feeling thirsty until they are already dehydrated. This is a reason why you should increase your water intake when you are ill or during the hot weather. The signs and symptoms of this condition can be different at any age.
- Signs and symptoms of dehydration in infants or young children :
- Listlessness or irritability
- Sunken soft spot on top of skull
- Sunken eyes, cheeks
- No wet diapers for three hours
- No tears when crying
- Dry mouth and tongue
- Signs and symptoms of dehydration in adults:
- Dark – colored urine
- Extreme thirst
Your doctor can diagnose dehydration on the basis of physical symptoms and signs. Also when we are dehydrated, we have low blood pressure, especially when we move from a lying to a standing position, a reduced blood flow to your extremities and a faster normal heart rate. If you have noticed that you or some from your family cannot keep down fluids or it has black or bloody stool, then you should visit your doctor as soon as possible. Also if you or some from your family has had diarrhea for 24 hours or more, then you should visit your family doctor. Also you should visit your family doctor if you are much sleepier or less active than usual or you are disoriented or irritable.
Causes of dehydration
In some cases dehydration occurs for simple reasons such as when you do not drink enough because you are busy or sick or because you lack access to safe drinking water when you are camping, hiking or traveling. Also there are other causes for dehydration such as
- Increased urination: This cause can be due to uncontrolled or undiagnosed diabetes. There are some medications such as blood pressure medications or diuretics which can also lead to dehydration because they cause you to urinate more. 
- Excessive sweating: When we sweat, then we lose water. If we do vigorous activity and we do not replace the fluids which we have lost, then we can become dehydrated. Hot and humid weather are increasing the amount we sweat and the amount of fluid we lose.
- Fever: If we have higher fever, then we have increased chances to become dehydrated. This problem is worsening if we have a fever in addition to vomiting and diarrhea. 
- Diarrhea, vomiting: Severe and acute diarrhea (this is a type of diarrhea which comes on suddenly and violently) can cause a tremendous loss of electrolytes and water in a short amount of time. If we have vomiting along with diarrhea, then we lose even more minerals and fluids. 
Risk factors: Every single person can become dehydrated, but there are certain people who have increased risk of becoming dehydrated such as
- People who work or exercise outside 
- People with chronic illnesses
- Older adults 
- Infants and children 
Complications: Dehydration can lead to serious complications such as
- Low blood volume shock (hypovolemic shock)
- Seizures 
- Urinary and kidney problems 
- Heat injury 
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