Dehydration signs: when fluids are not enough

Thirst, dark urine, reduced urination and a dry mouth can indicate dehydration. NHS guidance highlights greater vulnerability in young children and older adults, with vomiting, diarrhoea and heat increasing fluid loss.

Small frequent sips may be easier when nauseated. A pharmacist can advise on oral rehydration solution when vomiting or diarrhoea causes losses; it replaces salts as well as water.

Persistent dizziness on standing or reduced urination needs urgent advice. Confusion, breathing difficulty or being difficult to wake requires emergency care rather than simply trying to give more water.