Dehydration
Dehydration was a medical condition in which a body experienced an excessive loss of water. It was also a common symptom of transporter psychosis. ()

Common symptoms of dehydration included increased thirst and tiredness. () In some humanoids (such as Arkonians), dehydration caused acute cellular breakdown which increased the risk of transporter accidents. ()

When in an environment conducive to dehydration (such as a desert), breathing through one's nose helped to prevent the body from losing too much water. Captain Jean-Luc Picard recommended this to Wesley Crusher when the pair crash-landed on the moon Lambda Paz in 2367. ()  

Neodextramine solution was a medicine that could be used to treat dehydration. After Harry Kim was forced to return to the  from  in 2371, he suffered from dehydration in his shuttle. Upon returning, he was given a neodextramine solution. ()

After finding Bruce Maddox in captivity on Freecloud, Jean-Luc Picard visually diagnosed him as having suffered from dehydration and exposure. ()

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de:Dehydrierung
Medical conditions