Have someone call for immediate medical assistance while you begin cooling the affected person. The CDC recommends the following:
- Get the person to a shady area.
- Cool the person rapidly, using whatever methods you can, for example:
- Immerse the person in a tub of cool water
- Place the person in a cool shower
- Spray the person with cool water from a garden hose
- Sponge the person with cool water
- If the humidity is low, wrap the person in a cool, wet sheet and fan him or her vigorously
- Monitor body temperature and continue cooling efforts until the body temperature drops to 101°–102°F.
- If emergency medical personnel are delayed, call the hospital emergency room for further instructions.
- Do not give the person alcohol to drink.
- Get medical assistance as soon as possible.
Source: Centers for Disease Control (CDC). For more information see the CDC Web site.