Staying hydrated is a very important thing. If you’re dehydrated, you could feel dizziness, vomit, and you could possibly faint or get a fever. Suggested treatments are sipping water, drinks containing carbohydrates/electrolytes, sucking on something cool, and keeping the room cold, though using ice packs on the dehydrated person’s skin is highly not recommended.

Info was taken from:

http://www.webmd.com/a-to-z-guides/dehydration-adults