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What is Dehydration?

Dehydration happens when your body loses more fluid than it is taking in.

It’s completely normal to lose fluid throughout the day, from breathing, sweating, tears and going to the toilet and you usually replace it through whatever you drink and eat.

However, sometimes you may lose too much water, or not eat or drink enough, causing dehydration. For example, if you have recently been ill and suffered from diarrhoea or vomiting, then you may become dehydrated, as your body is not used to losing that much fluid.

If you think you are dehydrated, our doctors can help. However, if you, or the person you think may be suffering is showing the following signs, they could have severe dehydration and you should call 999 or go straight to hospital:

  • Feeling lethargic
  • Confusion, feeling disoriented
  • Dizziness when you stand up
  • Not passing urine for a period of eight hours
  • A weak pulse
  • A rapid heartbeat or breathing
  • Fainting or seizures
  • Are too ill to be able to drink fluids, or can't keep fluids down

Dehydration in children and babies

Children and babies can get dehydrated quickly, so make sure they’re drinking plenty of fluid day-to-day. If left untreated, it can also get serious quickly.

If it’s a child or baby who you think could be dehydrated, take them to A&E, or see a GP urgently if they are showing any of the following signs:

  • A rapid heartbeat or breathing
  • Have no tears when they cry (or very few)
  • Drowsiness
  • Floppiness
  • Irritability
  • If they have a sunken fontanelle (the soft spot on their head)
  • Their mouth is dry
  • Their urine is dark yellow in colour
  • Reduced wet nappies
  • Their hands and feet are cold and mottled
  • Drinking less than 50% of their normal intake

You should also speak to a GP if your baby has been sick three times or more in 24 hours or had multiple episodes of diarrhoea in the last 24 hours.

A doctor will be able to assess how dehydrated your baby is and hospital treatment may be required to bring their fluid levels back to normal, healthy levels.

Dehydration symptoms

The symptoms of dehydration may be mild or severe - this will depend on how much fluid you have lost. For mild dehydration, things to look out for include:

  • Feeling thirsty
  • Urine that is dark yellow in colour
  • Light-headedness or feeling dizzy
  • Lethargy
  • A dry mouth
  • Passing urine in small amounts

Dehydration may also have some psychological symptoms, including:

  • Feeling worried, tense or fearful
  • Trouble concentrating
  • Bad mood
  • Confusion

You can usually combat the symptoms of mild dehydration by drinking fluids to replace those you have lost. However, ifi you are seriously dehydrated, you should seek medical attention.

If you’re feeling poorly, you may not want to eat or drink, which can lead to dehydration, or you may not be able to keep fluids down.

Elderly people may not recognise the symptoms of dehydration in themselves and they're unable to retain as much fluid as younger people.

Likewise, people who have chronic illnesses – we’ll cover some of these below, but, for example, poorly managed diabetes can lead to passing urine a lot.

Dehydration treatment

You can increase your fluid level intake if you think you are dehydrated, but you should contact a GP if your symptoms continue, or go to hospital if you are showing severe symptoms.

At Push Doctor, our GPs can talk through how you feel, which will help our doctors diagnose whether there is anything underlying that is causing your dehydration and recommend the right treatment.

The doctor will be able to advise you on the best drinks for your dehydration too. These may include water and fruit juices, which will help to get both your fluid and sugar levels back up. Oral rehydration solutions (ORS) are available, which you may need to replace lost salt, sugar and minerals as quickly as possible.

The only way to treat dehydration is to replace lost fluid by either drinking more fluid or by seeking medical treatment for re-hydration, so it is very important you do not leave it untreated.

How can you prevent dehydration?

You can keep yourself hydrated by drinking water regularly throughout the day. If the weather is hot, you have been exercising, or you are ill, then you should increase the amount of water you drink if you can. This is particularly important for children and babies.

If you play a lot of sports, or exercise for long periods of time, it can result in a loss of bodily fluid, mainly though sweating. This makes people who participate in strenuous exercise more susceptible to dehydration, so make sure you're taking in enough water when you're active.

Read more about how much water you should be getting here.

How can Push Doctor help?

You can see a GP about your dehydration symptoms at a time that suits you. Our doctors are available 7 days a week and can offer you the advice, diagnosis and treatment you may need. They can also refer you to a specialist for further investigation or tests if required.