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Effervescent phosphate and calcium tablets – new information for parents and carers

Medicines for Children has published new information to help parents and carers when giving phosphate and calcium supplements to their children using effervescent tablets. Children and babies may need to be given extra phosphate or calcium for many different reasons and this information explains step-by-step how to make up the mixture and how to give the right amount to your child.

March 9, 2023

Effervescent tablet dispersing in glass of water

  • Effervescent tablets are designed to break up on contact with liquid such as water or juice, often causing the tablet to dissolve into a solution.
  • Effervescent tablets are widely used when giving calcium or phosphate supplements to children because liquid medicines are not always available.
  • Babies and children often need to be given ‘part tablet doses’ of effervescent tablets, as they require only small amounts. This has led to the increased risks of sometimes being giving the wrong amount of medicine.
  • This new information explains step-by-step how to make the mixture and how to give the right amount to your child. The instructions have been developed in discussion with parents and carers.
  • To give these tablets, you will need to dissolve a tablet in a specific amount of water and then give a specific amount of the mixture to your child – these amounts are stated on the pharmacy label.

You can read the new information leaflet ‘How to give phosphate or calcium from effervescent tablets‘:

Effervescent phosphate and calcium leaflet image

Children may occasionally be given a liquid medicine containing phosphate or calcium, but these may have been imported from another country or they may not be licensed for use in children. You can read more about medicines not licenced for use in children here: