Oral rehydration salts

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Oral rehydration salts for dehydration

This leaflet is about the use of oral rehydration salts for dehydration.

This leaflet has been written specifically for parents and carers about the use of this medicine in children. Our information sometimes differs from that provided by the manufacturers, because their information is usually aimed at adult patients. Please read this leaflet carefully. Keep it somewhere safe so that you can read it again.

Name of drug

Oral rehydration salts
Brand names: Dioralyte®, Dioralyte® Relief, Electrolade®

Why is it important for my child to take this medicine?

Although diarrhoea in children usually gets better on its own, it causes loss of water and body salts. The right balance of salts and water is important for the body to work in a healthy way. If your child loses too much water, they may become dehydrated. In severe cases, this can be dangerous, especially in very young children, when it is difficult to see the signs of dehydration.
Your child may be dehydrated if they have any of the following:

  • fewer wet nappies, nappies that are lighter than usual, or an older child is urinating (weeing) less often (less than the usual 2–3 times per day)
  • they are less active than normal and become drowsy
  • a dry mouth
  • crying without tears
  • a sunken soft spot on the top of a baby’s head.

Oral rehydration salts do not treat the diarrhoea itself, but they replace the salts and water that are lost, and so reduce the effects of dehydration.

If your child has the above symptoms and they are not starting to get better after 2–3 days, contact your doctor or local NHS services (111 in parts of England; 0845 4647 in parts of England and Wales; 0845 24 24 24 in Scotland). 

What are oral rehydration salts available as? 

  • Oral powder: one sachet is mixed with 200 mL of tap water. All makes of oral rehydration salts contain some sugar.

When should I give oral rehydration salts?

Oral rehydration salts are usually given after each runny poo (diarrhoea). 

How much should I give?

Your doctor will work out the amount of oral rehydration salts (the dose) that is right for your child. If you have bought them from your pharmacy, the dose will be shown on the medicine label. Encourage your child to drink as much as they can of the recommended dose.

It is important that you follow your doctor’s instructions about how much to give.

How should I give it?

Oral powderOral powder: open the sachet and pour the contents into 200 mL of tap water (this must be cooled boiled water for babies aged under 1 year). Stir well until all the powder has gone and the mixture is clear or just slightly cloudy. Make sure your child drinks the full dose needed. If they cannot drink it all in one go, they can drink it over about 30 minutes. It may help to use a straw. 

Do not keep the solution for more than one hour at room temperature. If you keep it in a fridge you can keep it for 24 hours.

When should the medicine start working?

Oral rehydration salts should start working quickly and dehydration usually gets better within 3 to 4 hours.

What if my child is sick (vomits)?

Often, sickness and diarrhoea come together, with a tummy bug (gastroenteritis). If your child is being sick as well as having diarrhoea, make up the full amount of oral rehydration salts but give small amounts often (10–20 mL every 5–10 minutes), as large drinks can make your child sick. It is important that you make sure the full amount is still given over a longer time.

  • If your child is sick less than 30 minutes after drinking the oral rehydration salts, give them again.
  • If your child is sick more than 30 minutes after drinking the oral rehydration salts, you do not need to give them again until they have their next runny poo.

You will not harm your child by giving too much of the oral rehydration salts, so if you are not sure how much your child has kept down, because they are being sick, it is better to give more rather than less of the oral rehydration salts.

Any oral rehydration salts that you have mixed with water but have not used should be thrown away after one hour (unless stored in a fridge, where they may be kept for 24 hours). 

What if I forget to give it?

Give your child another dose as soon as you remember.

What if I give too much?

You will not harm your child if you give an extra dose of oral rehydration salts by mistake.

Are there any possible side-effects? 

We use medicines to make our children better, but sometimes they have other effects that we don’t want (side-effects). However, oral rehydration salts don’t often have any side-effects.

If you notice anything unusual and are worried, contact your doctor.
You can report any suspected side-effects to a UK safety scheme at http://yellowcard.mhra.gov.uk.

Can other medicines be given at the same time as oral rehydration salts?

  • You can give your child medicines that contain paracetamol or ibuprofen, unless your doctor has told you not to.
  • You must tell your doctor if your child has ever had an allergic reaction or other reaction to any medicine they have been given before. If you have forgotten to tell your doctor, check with the doctor or pharmacist before giving oral rehydration salts to your child.
  • Check with your doctor or pharmacist before giving any other medicines to your child. This includes herbal or complementary medicines.

Is there anything else I need to know about this medicine?

If your child is not able to keep down any fluids at all and is showing signs of becoming dehydrated (see above), contact your doctor straight away. 

  • If your child will not take the rehydration salts then try to give them water (cooled boiled water for babies aged under 1 year) or weak juice. Contact your doctor if they will not take any fluids.
  • In the first 24 hours, it is best for babies with diarrhoea not to have any feeds except breastfeeds. In older children, you should limit solid foods or milk for the first 24 hours, as this may make the diarrhoea get worse. If your child seems to be getting better, you can give them water or juice to drink as usual but continue to give the rehydration salts after every runny poo.
  • Normal feeding should be started again after 24 hours, as the diarrhoea gets better. Your child may have some mild diarrhoea for up to a month after having a tummy bug (gastroenteritis).

If your child’s diarrhoea is very bad and not getting better after 48 hours, and you are worried that your child is losing too much fluid, contact a doctor.

  • You should not use oral rehydration salts to treat diarrhoea for more than 2–3 days, unless your doctor has told you to.
  • You should only use water to mix with the oral rehydration salts; do not use milk or juice and never add extra sugar or salt. This is because the rehydration salts contain the right mix of water and salts to help the body best.
  • You must be careful to use the right amount of water to make up the medicine, as too much or too little can mean the salts in your child’s body are not properly balanced.

If your child has liver or kidney disease, you should not use oral rehydration salts unless your doctor has told you to.

General advice about medicines

  • If you are not sure a medicine is working, contact your doctor but continue to give the medicine as usual in the meantime.
  • Only give this medicine to your child. Never give it to anyone else. If their condition appears to be the same, they should see a doctor.
  • If you think someone else may have taken the medicine by accident, contact your doctor.
  • Make sure that the medicine you have at home has not reached the ‘best before’ or ‘use by’ date on the packaging. Give old medicines to your pharmacist to dispose of. 

Where I should keep this medicine?

  • Keep the sachets of medicine in a cupboard, away from heat and direct sunlight.
  • Make sure that children cannot see or reach the medicine.
  • Keep the medicine in the container it came in.

Who to contact for more information

Your doctor, pharmacist or nurse will be able to give you more information about oral rehydration salts and about other medicines used to treat dehydration.

You can also get useful information from: 
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