Dehydration

2-minute read

Dehydration happens when you haven’t got enough fluids in your body. If severe, dehydration can cause serious problems. If you think you or someone with you is severely dehydrated, get them to hospital.

What is dehydration?

You are dehydrated if your body doesn't have enough water to keep it working properly. It can happen when your body loses too much fluid, such as from excessive sweating.

What causes dehydration?

People can get dehydrated:

after strenuous exercise, especially in hot weather
after severe vomiting or diarrhoea
with a fever
after drinking too much alcohol
while taking certain medicines such as diuretics
as a complication of diabetes
if they don’t drink enough water

Anyone may become dehydrated, but babies, young children, older adults and people with long-term illnesses are at most risk.

Dehydration signs and symptoms

If you have mild to moderate dehydration, you might:

be thirsty
have a dry mouth, lips and tongue
have a headache
have dark urine, and not so much of it
be dizzy or light-headed, particularly when standing up

If you have severe dehydration, you might:

be extremely thirsty
have a very dry mouth
be breathing fast
have a fast heart rate and a low blood pressure
have a fever
have little or no urine
be irritable, drowsy or confused

Babies who are severely dehydrated have a sunken fontanel, the soft spot on top of a baby’s head.

Severe dehydration is a serious problem, especially in babies and young children.

Dehydration treatment

Mild dehydration can be fixed by drinking more fluids. The simplest approach is to put 6 teaspoons of sugar with half a teaspoon of salt in one litre of boiled water. Here are instructions. You can also buy premade solutions from the pharmacy. Avoid alcohol and caffeine, as they can make you more dehydrated.

Severe dehydration needs immediate medical treatment, usually in hospital where fluids are given through an intravenous drip.

Dehydration prevention

Make sure you drink enough water each day, and have extra to replace any fluid lost during hot weather, illness or exercise.

Drink lots of fluids or oral rehydration solution to treat mild to moderate dehydration. See your doctor or go to a hospital emergency room if you, your baby, child or elderly relative is severely dehydrated.