Dehydration

dehydrateddehydratedehydratingskin turgorhydrationdehydrateswater lossnervous breakdownthirstwater deprivation
In physiology, dehydration is a deficit of total body water, with an accompanying disruption of metabolic processes.wikipedia
937 Related Articles

Hypovolemia

hemorrhagic shockhypovolemic shockvolume depletion
Dehydration can cause hypernatremia (high levels of sodium ions in the blood) and is distinct from hypovolemia (loss of blood volume, particularly blood plasma).
Hypovolemia refers to the loss of extracellular fluid and should not be confused with dehydration.

Thirst

Effects of thirstdrowthfeeling thirsty
Loss of over ten percent of total body water can cause physical and mental deterioration, accompanied by severe thirst. The hallmarks of dehydration include thirst and neurological changes such as headaches, general discomfort, loss of appetite, decreased urine volume (unless polyuria is the cause of dehydration), confusion, unexplained tiredness, purple fingernails and seizures.
Continuous dehydration can cause acute and chronic diseases, but is most often associated with renal and neurological disorders.

Decompression sickness

the bendscaisson diseasebends
Mild dehydration can also be caused by immersion diuresis, which may increase risk of decompression sickness in divers.
It is beneficial to give fluids, as this helps reduce dehydration.

Diarrhea

diarrhoeadiarrheal diseaseschronic diarrhea
Excess free water or hypotonic water can leave the body in two ways - sensible loss such as osmotic diuresis, sweating, vomiting and diarrhea, and insensible water loss, occurring mainly through the skin and respiratory tract.
It often lasts for a few days and can result in dehydration due to fluid loss.

Fatigue

exhaustionOverexertiontiredness
A five to eight percent decrease can cause fatigue and dizziness. The hallmarks of dehydration include thirst and neurological changes such as headaches, general discomfort, loss of appetite, decreased urine volume (unless polyuria is the cause of dehydration), confusion, unexplained tiredness, purple fingernails and seizures.
Medical causes of acute fatigue include depression; chemical causes, such as dehydration, poisoning, low blood sugar, or mineral or vitamin deficiencies.

Vomiting

emeticvomitemesis
Excess free water or hypotonic water can leave the body in two ways - sensible loss such as osmotic diuresis, sweating, vomiting and diarrhea, and insensible water loss, occurring mainly through the skin and respiratory tract.
In severe cases, where dehydration develops, intravenous fluid may be required.

Confusion

mental confusionconfusedconfusing
The hallmarks of dehydration include thirst and neurological changes such as headaches, general discomfort, loss of appetite, decreased urine volume (unless polyuria is the cause of dehydration), confusion, unexplained tiredness, purple fingernails and seizures.

Body water

total body waterWaterfluid
In physiology, dehydration is a deficit of total body water, with an accompanying disruption of metabolic processes.
The loss of the body water component of body fluid is specifically termed dehydration.

Fluid replacement

fluid resuscitationhydrationrehydration
Dehydration can be life-threatening when severe and lead to seizures or respiratory arrest, and also carries the risk of osmotic cerebral edema if rehydration is overly rapid. In some cases, correction of a dehydrated state is accomplished by the replenishment of necessary water and electrolytes (through oral rehydration therapy or fluid replacement by intravenous therapy).
Oral rehydration therapy (ORT) is a simple treatment for dehydration associated with diarrhea, particularly gastroenteritis/gastroenteropathy, such as that caused by cholera or rotavirus.

Urine

urinaryhuman urinepiss
The hallmarks of dehydration include thirst and neurological changes such as headaches, general discomfort, loss of appetite, decreased urine volume (unless polyuria is the cause of dehydration), confusion, unexplained tiredness, purple fingernails and seizures.
Dark urine is a sign of dehydration.

Diuresis

osmotic diuresisforced diuresisimmersion diuresis
Mild dehydration can also be caused by immersion diuresis, which may increase risk of decompression sickness in divers. Excess free water or hypotonic water can leave the body in two ways - sensible loss such as osmotic diuresis, sweating, vomiting and diarrhea, and insensible water loss, occurring mainly through the skin and respiratory tract.
Osmotic diuresis results in dehydration from polyuria and the classic polydipsia (excessive thirst) associated with DM.

Epileptic seizure

seizureseizuresepileptic seizures
The hallmarks of dehydration include thirst and neurological changes such as headaches, general discomfort, loss of appetite, decreased urine volume (unless polyuria is the cause of dehydration), confusion, unexplained tiredness, purple fingernails and seizures. Dehydration can be life-threatening when severe and lead to seizures or respiratory arrest, and also carries the risk of osmotic cerebral edema if rehydration is overly rapid.
Dehydration can trigger epileptic seizures if it is severe enough.

Plasma osmolality

Hypo-osmolalityserum osmolalityblood osmolality
A Cochrane review on this subject defined water-loss dehydration as "people with serum osmolality of 295 mOsm/kg or more" and found that the main symptoms in the elderly were expressing fatigue, missing drinks between meals and bioelectrical impedance analysis.
Osmolality of blood increases with dehydration and decreases with overhydration.

Terminal dehydration

dehydrationrefusal of food and fluids
Terminal dehydration is dehydration to the point of death.

Oral rehydration therapy

oral rehydration solutionoral rehydration saltsHydrational fluid
Mild dehydration is characterized by thirst and general discomfort and is usually resolved with oral rehydration. In some cases, correction of a dehydrated state is accomplished by the replenishment of necessary water and electrolytes (through oral rehydration therapy or fluid replacement by intravenous therapy).
Oral rehydration therapy (ORT) is a type of fluid replacement used to prevent and treat dehydration, especially that due to diarrhea.

Cholera

Asiatic choleracholera epidemicA cholera epidemic breaks out
Diarrhea can be so severe that it leads within hours to severe dehydration and electrolyte imbalance.

Syncope (medicine)

syncopefaintingfainted
For severe cases of dehydration where fainting, unconsciousness, or other severely inhibiting symptom is present (the patient is incapable of standing or thinking clearly), emergency attention is required.
This is often due to medications that a person is taking but may also be related to dehydration, significant bleeding or infection.

Electrolyte

electrolyteselectrolyticionic solution
When such large amounts of water are being lost through perspiration, electrolytes, especially sodium, are also being lost. In some cases, correction of a dehydrated state is accomplished by the replenishment of necessary water and electrolytes (through oral rehydration therapy or fluid replacement by intravenous therapy).
Serious electrolyte disturbances, such as dehydration and overhydration, may lead to cardiac and neurological complications and, unless they are rapidly resolved, will result in a medical emergency.

Homeostasis

homeostaticequilibriumimmunomodulation
In humans, dehydration can be caused by a wide range of diseases and states that impair water homeostasis in the body.
The body water homeostat can be compromised by the inability to secrete ADH in response to even the normal daily water losses via the exhaled air, the feces, and insensible sweating.

Intravenous therapy

intravenousintravenouslyinjection into a vein
In some cases, correction of a dehydrated state is accomplished by the replenishment of necessary water and electrolytes (through oral rehydration therapy or fluid replacement by intravenous therapy).
In cases in which a choice between intravenous therapy and oral treatment may be made to achieve the same outcome, such as in the case of mild or moderate dehydration treatment (assuming oral rehydration therapy is an option), then one should avoid using intravenous therapy in place of the less invasive oral option.

Dryness (medical)

drynessdrydry eyes
More generalized dryness can be caused by e.g. dehydration (that is, more general loss of body fluids), anticholinergic drugs and Sjögren syndrome.

Metabolism

metabolicmetabolizedmetabolic pathways
In physiology, dehydration is a deficit of total body water, with an accompanying disruption of metabolic processes.

Underwater diving

divingdiversdiver
Mild dehydration can also be caused by immersion diuresis, which may increase risk of decompression sickness in divers.

Dizziness

dizzydisequilibriumgiddiness
A five to eight percent decrease can cause fatigue and dizziness.

Comfort

discomfortcomfortableconsolation
Mild dehydration is characterized by thirst and general discomfort and is usually resolved with oral rehydration.