The Sierra Club's Annual One Day Hike
–  Since 1974  –

Washington, DC to Harper's Ferry, WV
–  50K • 100K  –

CSS Nested Menus


  Training Overview

  Training Hikes

  Tips on Training

  Trail First Aid

        Blister Care




        Get Trained

Trail First Aid – Dehydration

Source: The Comprehensive Guide to Wilderness First Aid, by Clifton Castleman, WEMT.

Thirst is the first sign that you are becoming dehydrated; and even mild dehydration can sap your energy and turn a fun hike into an ordeal.

Dehydration happens when your body does not have enough water as a result of heavy sweating, hard exercise, or sickness. It is especially likely to occur if you are hiking in hot weather and direct sunlight, though any time you are exercising hard and sweating a lot, you risk becoming dehydrated.

- How the Body Uses Water -

Preventing Dehydration

It is a lot easier to stay hydrated than to reverse dehydration, because if you are sweating heavily and become dehydrated, you may be losing water faster than your body can absorb the liquid you drink. In order to prevent dehydration, which can lead to life-threatening conditions if ignored, it is vital to replenish both the water and the electrolytes (salts) that your body loses through sweat and respiration.

  • Carry 2-4 quarts of water when hiking and sip it throughout the day.
  • Be sure urine is “clear and copious,” an important indicator of good hydration.
  • Eat salty snacks at each support station and on the trail in order to replenish your body’s lost electrolytes. Bananas & oranges will help keep up potassium and calcium levels, while trail mix and pretzels provide an extra boost in sodium as well as carbs. Peanuts (and other nuts) as well as watermelon are all excellent sources of protein.
  • Pay attention to environmental conditions and try to avoid direct sun if possible. In very hot weather, hikers typically lose around one half to one quart of fluid per hour.
  • Watch children and older adults closely for signs of a dry mouth, reduced urine output, and dark yellow urine, as they are at a much higher risk for dehydration.
  • Avoid caffeinated beverages, soft drinks, sugary drinks, and alcohol; as these drinks sap your body’s fluids and may make you vomit.

Know the Signs of Dehydration

An important early indicator of dehydration, along with dark yellow or brown urine. For mild or moderate dehydration, additional symptoms include:

  • Headache
  • Dry mouth
  • Increased thirst
  • Light-headedness that is relieved by lying down
  • Lethargy
  • Irritability

Severe dehydration can be very serious if a person begins to go into shock. Severely dehydrated people may be anxious; confused; faint or sleepy; have a weak, rapid pulse; and cold clammy or hot dry skin. They may even lose consciousness.

Treating Dehydration

When treating mild or moderate dehydration, slowly try to replace lost fluids while halting further loss of fluid from the body.

  • Get victims out of direct sunlight and out of the heat if possible, and remove excess clothing to reduce sweating.
  • Have them SIP water or an oral rehydration solution (STAY AWAY from sports drinks like Gatorade) to replenish their body’s fluids and electrolytes.
  • Encourage them to rest and to SLOWLY continue drinking fluids.

For severe dehydration, seek medical attention immediately at the nearest support station.

Copyright © 2014