India
Metabolic Medicine · 4 min read

Dehydration

Learn about Dehydration, its reported features, relevant specialists, and questions to discuss at a medical consultation.

Also known as: Thirst

Compiled from public sources
Text selected and arranged from MedlinePlus (US National Library of Medicine) health topic. It describes the condition as those sources do; it has not been rewritten for India.
01 Oct 2026
Not medically reviewed
No registered doctor has reviewed this page. Use it to decide who to see and what to ask — not to diagnose or treat.
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This is not medical advice. If symptoms are severe, sudden or getting worse, call 112 (or 108 for an ambulance) or go to the nearest emergency department.

The sources compiled here do not cover: prevalence. Ask the treating doctor about these.

What is dehydration?

From: MedlinePlus, National Library of Medicine

Dehydration is a condition caused by the loss of too much fluid from the body. It happens when you are losing more fluids than you are taking in, and your body does not have enough fluids to work properly.

What causes dehydration?

From: MedlinePlus, National Library of Medicine

You can become dehydrated because of:

  • Diarrhea
  • Vomiting
  • Sweating too much
  • Urinating too much, which can happen because of certain medicines and illnesses
  • Fever
  • Not drinking enough water or other fluids

Who is more likely to develop dehydration?

From: MedlinePlus, National Library of Medicine

Certain people are more likely to develop dehydration:

  • Older adults. Some people lose their sense of thirst as they age, so they don't drink enough fluids.
  • Infants and young children, who are more likely to have diarrhea or vomiting
  • People with chronic illnesses that cause them to urinate or sweat more often, such as diabetes, cystic fibrosis, or kidney problems
  • People who take medicines that cause them to urinate or sweat more
  • People who exercise or work outdoors during hot weather

What are the symptoms of dehydration?

From: MedlinePlus, National Library of Medicine

In adults, the symptoms of dehydration include:

In infants and young children, the symptoms of dehydration include:

Dehydration can be mild, or it can be severe enough to be life-threatening. Get medical help right away if the symptoms also include:

  • Feeling very thirsty
  • Dry mouth
  • Urinating and sweating less than usual
  • Dark-colored urine
  • Dry skin
  • Feeling tired
  • Dizziness
  • Dry mouth and tongue
  • Crying without tears
  • No wet diapers for 3 hours or more
  • A high fever
  • Being unusually sleepy or drowsy
  • Irritability
  • Eyes that look sunken
  • Confusion
  • Fainting
  • Lack of urination
  • Rapid heartbeat
  • Rapid breathing
  • Shock

How is dehydration diagnosed?

From: MedlinePlus, National Library of Medicine

To find out if you dehydration, your health care provider will:

Your provider may also order tests, such as:

  • Do a physical exam
  • Check your vital signs
  • Ask about your symptoms
  • Blood tests to check your electrolyte levels, especially potassium and sodium. Electrolytes are minerals in your body that have an electric charge. They have many important jobs, including helping to keep a balance of fluids in your body.
  • Blood tests to check your kidney function.
  • Urine tests to check for dehydration and its cause.

What are the treatments for dehydration?

From: MedlinePlus, National Library of Medicine

The treatment for dehydration is to replace the fluids and electrolytes that you have lost. For mild cases, you may just need to drink lots of water. If you lost electrolytes, sports drinks may help. There are also oral rehydration solutions for children. You can buy those without a prescription.

Severe cases may be treated with intravenous (IV) fluids with salt in a hospital.

Can dehydration be prevented?

From: MedlinePlus, National Library of Medicine

The key to preventing dehydration is making sure that you get enough fluids:

  • Drink enough water every day. Each person's needs can be different, so ask your health care provider how much you should be drinking each day.
  • Avoid drinks that have sugar and caffeine.
  • Drink extra fluids when the weather is hot, especially if you are exercising or working outside. If you are losing a lot of minerals in sweat, sports drinks can help you. But some sports drinks have lots of sugar, so be careful not to drink too much of them.
  • Get extra fluids when you are sick. If you are having trouble keeping liquids down, you can try taking small sips of water or sucking on ice chips.

Which doctor should you see?

The suggested department for discussing Dehydration is Metabolic Medicine, with a metabolic specialist / clinical geneticist as the relevant type of clinician. Paediatrician (children) or physician (adults), with metabolic specialist / clinical geneticist referral.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

  • Is a biochemical or molecular result needed to clarify the diagnosis?
  • Does this condition require an individual plan for illness or reduced food intake?
  • Should nutrition advice come from a specialist metabolic dietitian?

Treatment discussions and follow-up

Where the source describes treatments, these are an overview of possible care, not a prescription for an individual. Ask which option applies to the confirmed diagnosis, what benefit is expected, what adverse effects to watch for and how progress will be assessed. Availability, approvals and local practice can differ from the country described in the source.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.

Find a doctor for Dehydration

This condition is usually assessed by a metabolic specialist / clinical geneticist. The Doctor Index does not list that speciality yet. A family physician or paediatrician can examine, arrange first tests and refer to the right specialist centre.

All metabolic medicine conditions →

Sources

Source: MedlinePlus, National Library of Medicine. Orphadata Science: Free access data from Orphanet. © INSERM 1999; July 2026 data, CC BY 4.0. This product uses the Human Phenotype Ontology (hp/releases/2026-09-01). Only sources listed for this article apply. Source material has been selected and arranged; HPO definitions are reproduced without alteration. No source organisation endorses this compilation. Köhler S et al. The Human Phenotype Ontology project: linking molecular biology and disease through phenotype data. Nucleic Acids Research 2014;42(D1):D966–D974. doi:10.1093/nar/gkt1026.

General information, not advice about your situation. Errors can be reported through the corrections process. Reference TDI-C-0712.