This is to make sure all the bacteria are killed off. Your child may seem better after two or three days, but the illness is more likely to return if you don't finish all the medicine. Keep a note of the name of the medicine so you can tell your GP in the future. If you buy medicines at the pharmacist, always say it's for a young child. Give your child's age.
Some medicines are for adults only.
Always follow the instructions on the label or ask the pharmacist if you're unsure. Ask for sugar-free medicines if they are available. Look for the date stamp. Take them back to the pharmacy to be destroyed. Only give your child medicine given by your GP or pharmacist.