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

The solution contains water and salts in a balance that helps the gut absorb fluid. It does not destroy norovirus or stop every episode of vomiting and diarrhoea. A dry mouth, thirst, darker urine, headache or light-headedness may gradually ease as fluid balance improves. If vomiting returns, the body may lose fluid faster than it can absorb it.

Prepare the product exactly as directed and take frequent small sips. After vomiting, pause briefly, then restart with smaller amounts rather than drinking a large volume at once. Continue breastfeeding when relevant, and eat small, plain meals when tolerated. Avoid relying on very sugary drinks, which may worsen diarrhoea. Monitor whether urination becomes more regular and whether alertness and thirst improve.

Seek urgent medical help for confusion, fainting, severe weakness, difficulty breathing, blood in vomit or stool, or severe abdominal pain. Contact a clinician promptly if fluids cannot be kept down, urination becomes very infrequent, or dehydration signs are not easing. Babies, older adults, pregnant people and anyone with a serious long-term condition can become dehydrated quickly and may need earlier assessment.

Ask which product and mixing instructions are suitable, how much to take after each loose stool or vomiting episode, and which warning signs should prompt an assessment for you or your child.