Got a headache? We all do from time to time, but a common trigger often gets overlooked: dehydration. When life is busy, it’s easy to forget to drink, and that nagging pain in your head may be a dehydration headache. But if you think chugging a glass of water will bring fast headache relief, think again; the truth can be more complex. We’ll help you understand how dehydration affects your body, discover dehydration headache symptoms and effective relief methods, uncover myths and learn expert-backed solutions for sustained hydration.
First, it’s important to note that ‘dehydration headache’ is not a class of headache. Most headaches are caused by some combination of factors. In addition to dehydration, these include lack of sleep, alcohol, caffeine withdrawal, stress and more. That’s why we don’t classify headaches by causes, but by types, such as migraine, cluster or tension headaches.
A dehydration headache is therefore not a standalone diagnosis. Rather, the definition of dehydration headache is a headache that is a symptom of being dehydrated.
Dehydration occurs when you’ve lost more fluids than you’re taking in. You lose fluids through sweat, urine, breathing, tears and more. Eating and drinking usually replace those fluids, but sometimes the balance shifts. For instance, if you’re ill, you may lose fluids through vomiting or diarrhea and fail to replace them because you don’t feel like eating or drinking. Heat, exercise, caffeine and some medications may also contribute to dehydration.
When you become dehydrated, many things happen in your body. The volume of fluid in your cells and tissues shrinks. You also lose electrolytes like sodium and potassium that are necessary to hydration, muscle function and nerve impulses. This can cause your heart rate to speed up, your blood pressure to drop and your muscles to cramp or twitch. Severe or chronic dehydration strains your kidneys and can cause painful kidney stones. Dehydration also activates the pain networks in your central nervous system and can lower your pain threshold.
It’s thought that your brain also contracts as your tissues lose fluid. As it pulls away from your skull, it stretches the veins in the membranes of your brain and puts pressure on your nerves, causing a headache. Dehydration may also trigger pre-existing headache disorders, such as migraine.
Some types of headaches, like migraines, have warning symptoms like auras or nausea. Dehydration headaches don’t, but other symptoms of dehydration may precede a headache and give you an opportunity to rehydrate before head pain hits you. Following is a dehydration symptoms list:
Severe dehydration can also cause:
Dehydration headaches are also unlike tension, migraine and cluster headaches in that they don’t have a particular pain profile. In other words, they can be dull, sharp, throbbing or stabbing. They may be felt all over your head or only in one spot. This makes it difficult to tell what’s causing your headache unless you’re experiencing other dehydration symptoms.
The symptoms of mild dehydration can be very subtle and easy to ignore. Something as simple as a hard day at work may leave you tired, “out of it” and grumpy with a headache — all of which are also symptoms of dehydration. That means you may overlook hydration as a solution to your symptoms and, failing to address the underlying issue, worsen it.
The good news is that you don’t have to know you’re dehydrated before you treat it at home. When in doubt, drinking some healthy fluids and replacing electrolytes can’t hurt.
Anyone can become dehydrated if they lose more fluid than they take in, which means anyone can suffer from dehydration headaches. However, some people are at higher risk. Groups with greater dehydration risk factors include:
Chronic headache disorders affect 52 percent of people. Migraines alone affect about 15 percent of the population, while about 26 percent get tension headaches. And those numbers may be on the rise: from 1990 to 2021, the prevalence of tension headaches rose 38 percent.
Dehydration can significantly impact people who suffer from chronic headache disorders. Migraines, tension headaches and cluster headaches can all be triggered by dehydration. Worse, it can compound the negative impact of other triggers. For example, heat and exercise may trigger a migraine and cause dehydration that then worsens the headache. Some symptoms of chronic headache disorders, like nausea and vomiting, can cause dehydration, too. This relationship can result in a negative feedback loop that makes headaches more difficult to control.
Other chronic health conditions, such as celiac disease, colitis and Chron’s disease, put people at higher risk of becoming dehydrated. They may also be more seriously impacted by dehydration. Diabetes, for instance, causes high blood glucose levels that decrease your body’s hydration. Dehydration, in turn, can contribute to diabetes complications including kidney failure, ketoacidosis and diabetic coma. If you have a chronic health problem, you should take precautions to ensure you stay hydrated to avoid exacerbating your condition.
During pregnancy, amniotic fluid levels, a healthy placenta, good circulation and more depend on adequate hydration. Yet many factors, including morning sickness and increased urination, can make it more difficult to stay hydrated. Pregnant people therefore must take in more water than usual to support the increased demands on their bodies.
Dehydration during pregnancy can lead to a host of problems ranging from the annoying (constipation) to the dangerous (preterm labor). Unfortunately, dehydration symptoms mirror other common symptoms of pregnancy such as overheating, cramps and, of course, headaches. This makes it easy to overlook dehydration as a possible cause. The good news is that if you’re looking for natural ways to get rid of headache while pregnant, replenishing your fluids and electrolytes is a great place to start. And, to avoid chronic dehydration while pregnant, be sure to drink 64 to 96 ounces of water a day.
If you’re getting pregnancy headaches regularly, it’s important to talk to your medical provider. It may just be hormonal changes or the natural increase in blood volume. However, pregnancy headaches can be caused by chronic dehydration, stress, nutritional deficiencies and other problems that may require professional help to manage.
If your head is pounding thanks to dehydration, you want quick headache relief. When it comes to treatment for headaches, rehydrating should be your greatest concern. If the dehydration symptoms accompanying your headache are minor, this can safely be done at home. However, if you show signs of moderate to severe dehydration, it’s important to seek medical attention.
REHYDRATING WITH HEALTHY FLUIDS. The only way to treat dehydration is to replace fluids in your body. At home, this means drinking. It’s best to avoid caffeinated or sugary drinks and alcohol. Instead, reach for one of these:
REST. Dehydration often causes fatigue. Taking some time to rest and let the fluids rehydrate your body is important. Even if you don’t feel fatigued, dehydration headaches tend to feel worse when you shake your head or bend down. Resting in a cool place can prevent unnecessary discomfort.
COLD COMPRESSES. Although cold compresses don’t aid in rehydration, they have been shown to provide some relief from headache pain. Apply to your head or neck. If you use an ice pack, wrap it in a towel to avoid damaging your skin.
OVER-THE-COUNTER PAIN RELIEVERS. Pain relievers like acetaminophen, aspirin, ibuprofen and naproxen can provide headache relief while you wait for fluids to rehydrate you. Read labels carefully, as you shouldn’t take some OTC pain relievers if you take certain prescription medications or have some preexisting medical conditions.
If you can’t get rid of your symptoms or have more serious symptoms, urgent care can help. Urgent care is appropriate if you experience:
Children should visit urgent care if they have dry mouth, increased thirst, a slight decrease in urination, irritability or fatigue.
At BestMed Urgent Care, our providers are highly experienced at diagnosing dehydration. They will conduct a physical examination, discuss your symptoms and ask what you’ve tried. Then, they’ll create a treatment plan that may include oral rehydration or IV fluids. If you’ve been vomiting or have diarrhea, they may provide medication to treat these conditions. They will also discuss follow-up self-care, OTC medications and preventive measures. If your symptoms worsen, they may refer you to the emergency room.
If you have any of the following symptoms, you may be severely dehydrated and should visit a hospital emergency room immediately:
Children who exhibit sunken eyes, a lack of tears while crying, little or no urination in the past 8 hours, persistent vomiting or diarrhea or cool, dry skin should also go to the ER right away. If they are unresponsive, call 911.
Dehydration is also not the only medical condition for which headaches are a symptom. If your headache does not resolve within a few hours of rehydration, you should visit a medical professional. If you have a headache after a head injury or your headache is accompanied by fever, shortness of breath, stiff neck or rash, visit a healthcare professional right away. Headaches in these circumstances can indicate a concussion or other brain damage, meningitis or other neurological problems that require immediate attention.
Water is crucial to your wellness, and there are multiple changes you can make to stay hydrated and healthy. Preventing headaches and other side effects of dehydration begins by focusing on diet and routine check-ups.
From regulating your temperature, getting rid of waste and improving your blood circulation to cushioning your joints, aiding in digestion and keeping your cognitive skills sharp, water affects your body’s ability to function properly. Taking in enough water every day is the most important step you can take toward preventing headaches due to dehydration.
Adults generally require 11.5 to 15.5 cups of fluid a day. You get about 20 percent of your fluid requirements from eating a healthy diet and the remaining 80 percent (9.25 to 12.5 cups) through what you drink. You may require more water if you:
When it comes to what you drink, water is always good but milk, coconut water, broth and herbal teas are also great choices. Sports drinks, juices, coffee and soda can contribute to hydration in moderation but read labels carefully to avoid taking in too much sugar, caffeine and calories.
Eating recommended amounts of fruits and vegetables every day is one of the best ways you can ensure you are taking in enough water through your diet. Melon, apple, tomato, berries, leafy greens, carrots and sweet potatoes are just some of the fruits and veggies that contribute to healthy hydration. Healthy foods like vegetable soup, yogurt, cottage cheese and salmon are also water-rich.
Routine health check-ups with a primary care provider are an important part of staying healthy long term. Regular check-ups ensure that you stay up to date on vaccines and medication needs, keep any existing conditions under control and get regular screenings to detect new health problems before they become critical.
Since headaches and dehydration can both be symptoms of many chronic illnesses, it’s important to tell your health provider if you’ve been experiencing them. Your provider will be able to ask additional questions, conduct screenings, take blood and do other tests that can help them pinpoint what might be going on and develop a treatment plan.
Whether your headaches turn out to be migraines or a symptom of dehydration caused by diabetes, knowing how to treat your condition can significantly improve how you feel and may prevent complications that could take away from your quality or quantity of life. Even if you aren’t experiencing specific symptoms, your primary care provider can make lifestyle recommendations, such as how much you should be drinking and how to get more liquids in your diet, that can improve your overall health.
Myth: Drink More Water, Get Instant Relief
When you have a dehydration headache, you want instant relief. Unfortunately, it’s not always as simple as quickly drinking a glass of water.
When you’re dehydrated, drinking too fast can make your stomach hurt, so sip slowly. Once you’re dehydrated, it takes time for fluids to rehydrate your whole symptom. It may take a couple hours after you replenish fluids before your headache goes away. And, if you’re severely dehydrated, water may not be enough to rehydrate you. You may need to replenish electrolytes, as well.
Myth: Sports Drinks are Best for Rehydration
It’s true that sometimes you need to replace electrolytes like potassium and sodium along with water. Sports drinks tout replacing electrolytes but don’t call attention to the amount of sugar and calories they contain. Find a sports drink with low sugar and calories, drink them in moderation or get electrolytes in another way. A pinch of salt in water, a banana with a glass of water or unsweetened coconut water are all good options.
Myth: You Shouldn’t Take Pain Medication When You’re Dehydrated
It’s okay to take over-the-counter pain relievers to reduce the discomfort of a dehydration headache as long as you take them with plenty of water to rehydrate your body. Some pain medications impact your kidneys or liver and can make dehydration worse if you don’t also increase your fluid intake. Be sure to read instructions carefully.
Myth: It’s Only a Dehydration Headache if You’re Also Thirsty
You don’t always feel thirsty when you’re dehydrated. Determining the cause of a headache is sometimes an iterative process. If your headache is accompanied by other symptoms of dehydration or goes away within an hour or two of drinking more fluids, dehydration was likely the culprit. If your headache doesn’t respond to fluids or you’re getting headaches regularly, something else may be to blame. Make an appointment with a medical provider to see what might be wrong.
Headaches are one of the most common symptoms of dehydration and can be an early indicator that your body needs more fluids. They may or may not be accompanied by other common symptoms such as dry mouth, fatigue, dark urine or muscle cramps. Regardless, drinking water, coconut water or a rehydration drink when you have a headache is a good early intervention that won’t cause harm even if something other than dehydration is to blame. If you have symptoms of moderate dehydration like dizziness, lightheadedness or vomiting, visit the BestMed Urgent Care nearest to you for additional help. Visit the ER for serious symptoms.
Avoid dehydration headaches by making minor changes to your diet to ensure you stay hydrated. In most cases, this can be done simply by taking in the recommended daily amounts of water, fruits and vegetables. If you exercise strenuously, work or live in the heat or have certain medical conditions, ask your medical provider for customized recommendations.
You should also see a provider if you have persistent headache problems. Recurring headaches can sometimes point to more serious underlying conditions. Taking a proactive approach can improve your quality of life and avoid potentially serious complications.