Water accounts for almost 70% of the human body. Dehydration refers to the loss of excess body fluid, and it can occur when the loss of water is greater than its intake. However, dehydration also refers to the loss of electrolytes, which are required for carrying out several vital functions of the body. A considerable amount of water is lost in activities like urination, sweating, and even breathing. If the amount of fluid lost is not replenished with adequate intake of water or fluid, then it can result in dehydration. If the level of water in the body gets reduced below the level required for maintaining the vital functions, it can manifest in several symptoms, including headaches. So, a dehydration headache is basically a headache that develops when the level of water in the body reduces significantly. Other than headaches, dehydration can cause fatigue, dizziness, muscle cramps, dry mouth, rapid heartbeat, and dry, flushed skin. What Causes a Dehydration Headache? As the name suggests, it is caused by the loss of excess fluid from the body or dehydration. But how exactly dehydration causes a headache is not very clear. It is assumed that when the level of water reduces in the body, the body tries to conserve the remaining water. To do so, it constricts the blood vessels, which in turn reduces the supply of oxygen and blood to the brain. Sometimes, there may be spasms of the blood vessels, which can reduce the supply of oxygen and blood to the brain. This in turn, can cause a headache. Moreover, the body loses some important electrolytes due to dehydration, which are crucial for maintaining the various functions of the body. Dehydration can result from a number of factors, including not drinking enough fluid. Sometimes, it can also be caused by the excessive intake of certain beverages like coffee and alcohol, which have diuretic properties. The overconsumption of coffee or alcohol combined with the inadequate intake of water can sometimes cause severe dehydration. A large amount of water is also drained out of the body while exercising, playing sports, and performing strenuous activities. In fact, dehydration can be one of the most important causes of headaches experienced after exercising. Even medications like diuretics, antihistamines, and calcium channel blockers can cause the loss of a considerable amount of water. Sometimes, dehydration can be associated with certain medical conditions like diabetes, and kidney and adrenal gland disorders. How to Get Rid of Dehydration Headaches The headache caused by dehydration can be felt on the front, back, or one side of the head. The pain can also be felt throughout the entire head. The pain is often worsened by activities like bending the head or moving it sideways. This headache can be alleviated by increasing the intake of fluid. However, dehydration also causes the loss of important electrolytes like potassium and sodium. Sports drinks and fruit juices can be helpful in replenishing the lost minerals or electrolytes. If the pain does not alleviate with sufficient fluid intake, then you can take the over-the-counter pain relievers. How to Prevent Dehydration Headaches? Drinking plenty of water is the most simple treatment for this condition. Usually, one should drink 8 to 10 glasses of water daily to replenish the water lost in the form of urine and sweat. Experts are of the opinion that one should drink about 40 ounce of water for per 100 pounds of body weight. However, the water requirement of the body can increase in certain circumstances. For example, intense physical activity or exercises can increase the water requirement of the body significantly. One should drink more water in warmer weather or climate, at high altitude, and in certain health conditions like cold or fever, diarrhea, vomiting, diabetes, kidney diseases, and adrenal disorders. One should drink more water after consuming caffeinated beverages and alcohol. People taking any kind of medications should also drink plenty of water throughout the day. To sum up, one should drink plenty of water on observing any of the symptoms of dehydration, in order to cure and prevent a severe headache. Many people think that thirst is the only symptom of dehydration, and so, if they are not thirsty, they are not dehydrated. This a completely wrong notion, as one can become dehydrated without feeling thirsty as well. One of the most important indicators of dehydration is a change in the frequency of urination, as well as the color of urine. If the urine is dark yellow in color, the volume is less, and the frequency of urination has reduced, then you are likely to be dehydrated. In such a situation, be sure to immediately replenish the body with water and fluids that contain electrolytes. Disclaimer: This article is for informative purposes only, and should not be treated as a substitute for professional medical advice.