Heat exhaustion symptoms hours later

Sweating during heat exposure can reduce fluid and salt stores, while the body may remain overheated after the activity ends. Dizziness, headache, nausea, weakness, thirst and heavy sweating may therefore persist or become noticeable later. A person who improves briefly and then worsens needs attention, because delayed symptoms are not proof that the problem is harmless. Learn about [Heat Exhaustion](/conditions/heat-exhaustion/) and [Heat Intolerance](/symptoms/heat-intolerance/).

Rest away from heat in loose clothing. Cool the neck, armpits and skin with damp cloths or a fan, and take small, regular sips of water or an oral rehydration drink if fully alert. Avoid strenuous activity until you feel back to normal. Keep someone nearby to notice confusion, fainting or increasing weakness. Track urine output and colour; dark urine can indicate ongoing fluid loss. Read more about [Dark Urine](/symptoms/dark-urine/).

Get emergency help for confusion, collapse, seizure, trouble breathing, inability to swallow or very hot skin with altered alertness. Arrange urgent assessment if vomiting stops you drinking, symptoms are worsening hours later, urination is markedly reduced, or cooling and fluids do not bring clear improvement.

Ask how long to avoid heat and exercise, whether an oral rehydration drink is appropriate for you, and whether medicines or chronic conditions change your fluid plan. Mention every symptom that appeared after the heat exposure, even if it seemed minor at first.