How do I know if I'm dehydrated?

Concerns & risks

You were trying to get through a hot, busy day, but now you've got a headache, dark pee and you feel kind of dizzy.

Dehydration can get serious, especially in heat.

Causes & evidence

Signs include thirst, dark urine, dizziness and headache. See dehydration. If symptoms are severe, sudden or getting worse, contact a doctor or emergency services.

What to do

1. Move to shade or a cool place.
2. Sip water or an oral rehydration drink.
3. Rest.
4. Get help for confusion, fainting or no urination.

Common mistakes: Common mistakes: waiting until you're very thirsty to drink. Thirst can lag behind, especially in older adults. Sports, heat and illness with vomiting or diarrhea raise fluid needs. Sip steadily rather than chugging a lot at once. Watch for very little urine, confusion or fainting, which need medical help. Infants and older adults can become dehydrated faster, so keep an extra eye on them.

Speed Man tip: Urine color is a quick check: pale yellow is the goal.

Wrap-up: Dark urine and dizziness are signs. Cool down and sip fluids. Severe signs need care.