An increased thirst is normal in conditions such as hot weather, exercise, increased exertion, and similar situations. An abnormal or excessive thirst, also called polydipsia, can be the symptom of various disorders. Dehydration is one obvious cause, and this can be dangerous. Unexplained thirst is also a classic symptom of ...

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Feeling thirsty all the time and for no good reason isn't normal and should be investigated by your GP. Thirst is normally just the brain's way of warning that you're dehydrated because you're not drinking enough fluid. But excessive and persistent thirst (known as polydipsia) could be a ...1

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Simple causes of thirst include:

  • Normal. It could simply be normal thirstiness.
  • Dehydration
  • Heat exposure
  • Exercise or exertion
  • Reduced fluid intake
  • Fever. Many causes of fever will cause a mildly or moderately increased thirst.

Note that dehydration is a potentially ...

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Causes of Thirst

Common causes of thirst

Source: NHS Choices UK2 ...

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Differential Diagnosis of Thirst

Dry mouth: Dry mouth Some people think they're thirsty when they actually have a dry mouth. It's important to know the difference between the two because they can have different causes. For example, a dry mouth can be caused ...3

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Causes List for Thirst

Possible causes of Thirst (or similar symptoms) may include:4

... Causes List for Thirst »

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  1. Source: NHS Choices UK: conditions/ thirst/ 
  2. ibid.
  3. ibid.
  4. Source: Algorithmically Generated List

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Note: This site is for informational purposes only and is not medical advice. See your doctor or other qualified medical professional for all your medical needs.