Heat exhaustion dizziness: what to know and do

In hot conditions, your body sends more blood toward the skin and loses fluid through sweat. That combination can leave you light-headed, weak, nauseated or unsteady, especially after standing. Heat exhaustion may also occur with headache, thirst, heavy sweating and dark urine. Read more about [Heat Exhaustion](/conditions/heat-exhaustion/) and [Dehydration](/conditions/dehydration/).

Stop activity and move the person to shade or an air-conditioned place. Lay them down with legs raised if they feel faint, loosen extra clothing, and cool the skin with wet cloths or a fan. If they are awake and able to swallow, offer frequent small sips of cool water or an oral rehydration drink. Do not leave them alone or allow them to drive while dizzy. Review [Dizziness](/symptoms/dizziness/) if the sensation continues.

Call emergency services if the person becomes confused, faints, has a seizure, cannot drink, has trouble breathing, or is very hot with altered behaviour. Seek same-day medical care when dizziness persists after cooling and fluids, vomiting prevents drinking, or urine becomes very dark. Worsening symptoms can signal heatstroke or significant dehydration.

Ask whether medicines, pregnancy, heart conditions or a recent illness could increase heat risk. Ask how to replace fluids safely if you have kidney or heart disease, and when you can return to exercise or outdoor work.