Babies and children are at more risk of getting dehydrated. This means your body is losing more water than you take in. It can lead to serious health issues if not treated immediately. Minor dehydration includes: - Dizziness or light-headedness - Headaches - Nausea - Dark yellow or brown urine - Fewer wet nappies - Dry lips and mouth In children, you'll see signs which include: - Feeling thirsty - Lethargic - Feeling cold - Breathing fast or having a fast heart rate - Being irritable, tired, or confused In babies, signs of dehydration include: - A sunken soft spot (fontanelle) on top of their head - Sunken eyes - Few or no tears when they cry - Not having many wet nappies - Being drowsy or irritable