Dehydration - An Avoidable Migraine Trigger

by Teri Robert Patient Advocate

The human body is 65% water. Simply put, dehydration occurs as the result of excessive loss of water from the body — when we lose more water than we take in. It's a bit more complicated than that since the body loses valuable electrolytes as well. That's why sports drinks have become so popular; they replenish electrolytes as well as just fluid. Dehydration can be a major issue, both in and of itself and as a Migraine or headache trigger.

Many people mistakenly think dehydration occurs only in hot weather, and that you're not dehydrated if you're not thirsty. Both of these misconceptions lead to many cases of dehydration every year, some of them quite serious. Let's take a look at dehydration, what it does to the body, how to treat it, and — perhaps most importantly — how to prevent it.

Dehydration basics:

  • It takes an average of 64 to 80 ounces to replace the water our bodies lose in 24 hours.

  • Under normal circumstances, how much water we need depends a great deal on the volume of our perspiration and urine output.

  • Our bodies' need for water increases under circumstances such as:

    • warmer weather or climate

    • living at high altitudes

    • increased physical activity

    • when experiencing vomiting or diarrhea

    • when fevered

    • when you have a cold or the flu

    • if you have a chronic disease such as uncontrolled or untreated diabetes, kidney disease, alcoholism, cystic fibrosis, or adrenal disorders

    • if you are taking some medications. Always check your prescription information.

    • during long air flights

    • Losing as little as 1 to 2% of body weight can result in dehydration.

    • Losing 3 to 5% can negatively impact reaction time, concentration and judgment.

    • Losing 9 - 15% results in severe dehydration and is life-threatening.

    Symptoms of dehydration:

    • Excessive thirst

    • Fatigue

    • Muscle weakness

    • Headache (or, in the case of Migraineurs, Migraine)

    • Dizziness

    • Less frequent need to urinate and decreased output

    • Darker colored urine (should be nearly clear to pale yellow)

    • Confusion

    • Increased heart rate and respirations

    • Skin that doesn't snap back when pinched and released

    • Children may exhibit additional symptoms:

      • Absence of tears when crying

      • No wet diaper for three hours or longer

      • Irritability

      • Lethargy

      • Fever

    Treating dehydration:

    Dehydration should be confirmed by your doctor. Caught early, after confirming with your doctor, dehydration can usually be treated at home. Especially with children, your doctor's suggestions for treatment may vary depending on the cause and severity of the dehydration. Common treatments include:

    • Mild dehydration: rehydration by drinking fluids including sports drinks, which rehydrate by providing not only fluid, but also electrolytes and salt. In children, products such as Pedialyte may be recommended as it also contains carbohydrates to help absorption in the intestinal tract. Coffee, tea, and soda should not be used for dehydration as the caffeine in them can actually be dehydrating.

    • Moderate dehydration: rehydration may suffice, but IV fluids may be required.

    • Severe dehydration: Immediate action must be taken, treating the situation as a medical emergency. Hospital treatment is necessary for IV fluids to rehydrate more quickly and efficiently and to allow observation.

    Prevention, the best treatment:

    Obviously, it's better to prevent dehydration. Here are some steps you can take:

    • Drink plenty of fluids and eat foods high in water. Fruit contains the most water, followed by vegetables, meat, then grains with the least.

    • Choose your beverages wisely. Caffeine and alcohol can be dehydrating. For some people, too much fruit juice can cause diarrhea, which can be dehydrating.

    • If you're planning a day with more exercise than usual, begin hydrating the day before.

    • Sports drinks can help maintain electrolyte balance, but be aware of the sugars in them.

    • Plan outdoor activities for cooler parts of the day.

    • If you're organizing outdoor activities, provide shaded areas.

    • When you're ill, be sure to continue drinking fluids, and get additional fluids if you have a fever or are vomiting or have diarrhea. Call your doctor for help with vomiting or diarrhea if necessary.

    • Talk with your doctor about your medications and dehydration. Some medications can contribute to dehydration, and you may need to account for that.


    Learning to prevent and to recognize dehydration are essential. Don't let dehydration ruin your fun or make you more ill. Remember to take in as much fluid as you're losing each day. Talk with your doctor to see if any of your medications can contribute to dehydration so you can take that into account, if necessary.

Teri Robert
Meet Our Writer
Teri Robert

Teri Robert is a leading patient educator and advocate and the author of Living Well with Migraine Disease and Headaches. A co-founder of the Alliance for Headache Disorders Advocacy and the American Headache and Migraine Association, she received the National Headache Foundation's Patient Partners Award and a Distinguished Service Award from the American Headache Society.