How long does oral rehydration therapy take to work for rotavirus infection?

Rotavirus can cause repeated watery diarrhoea and vomiting, so losses may continue after rehydration begins. Oral rehydration solution supplies water and salts that the intestine can absorb; it does not remove the virus. Less thirst, a moister mouth, more alertness and more regular urination are useful signs that hydration is improving. Symptoms can fluctuate if vomiting or diarrhoea continues.

Mix the solution only as the instructions state. Give frequent small sips; for a child, use a spoon or syringe if that makes drinking easier. If vomiting happens, wait briefly and restart slowly. Continue breast or formula feeds as advised, and offer food when tolerated. Do not dilute the solution or substitute soft drinks. Keep checking urination, alertness, tears and the moisture of the mouth.

Get urgent help if there is unusual sleepiness, confusion, fainting, breathing difficulty, blood in vomit or stool, or severe pain. Arrange prompt medical assessment when a child has very few wet nappies, no tears, a sunken appearance around the eyes, or cannot keep the solution down. Infants and people with other medical conditions may need advice sooner because fluid loss can become serious.

Ask how to choose and prepare the solution, how to offer it after vomiting or diarrhoea, and which changes in urination or behaviour mean that your child needs an examination.