Dehydration may cause dizziness or vertigo. That said, dizziness can have many causes. In any case, if you think you might be dehydrated, drink fluids right away.

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Water is vital to our health and well-being. In fact, about 60 percent of our body weight is made up of water.

Dehydration happens when you lose more water than you take in. When this happens, your body doesn’t have enough water to effectively carry out critical tasks like breathing, digestion, and other essential functions.

Although you can become dehydrated simply by not drinking enough water, it can also happen due to:

There are several symptoms of dehydration. One of these is dizziness which can be felt in several different ways, including as a spinning sensation known as vertigo.

In this article, we’ll take a closer look at vertigo due to dehydration and other symptoms to look out for. We’ll also explore the steps you can take to prevent dehydration.

Dehydration can lead to dizziness. When you’re dizzy, you may feel:

If you’re dehydrated, it’s also possible that you could experience a specific type of dizziness known as vertigo. When you have vertigo, you feel as if you or your surroundings are spinning. Other sensations associated with vertigo include:

  • floating
  • swaying
  • tilting

When you experience dizziness or vertigo, you may also feel:

  • nausea
  • the need to sit or lie down
  • worsening symptoms when you stand or move

However, it’s important to note that there are other conditions besides dehydration that can cause vertigo, such as inner ear problems and migraine.

You may be wondering why vertigo happens when you’re dehydrated. Let’s examine this in more detail.

When you’re dehydrated, your body doesn’t have enough fluids to function effectively. This can have an impact on many parts of your body, including your circulation.

People who are dehydrated often have reduced blood pressure or lower blood volume. When this happens, blood may not reach your brain in the way that it should. This can lead to feelings of dizziness or vertigo.

Most of the time, the dizziness caused by low blood pressure isn’t a vertigo-like feeling. Instead, low blood pressure due to dehydration typically causes a lightheaded feeling, like you’d pass out if it got worse.

But there may be instances where low blood pressure could cause the spinning sensation of vertigo. It’s just not as common as feeling lightheaded.

Some other dehydration symptoms to watch out for include:

  • Thirst. Feeling thirsty is your body’s way of telling you that you need to drink more fluids.
  • Reduced urination. When you’re dehydrated, your body will signal your kidneys to retain fluids. Because of this, you’ll likely urinate less frequently.
  • Dark urine. If you’re well-hydrated, you urine is typically clear or pale yellow. Dark urine indicates that your urine has become more concentrated.
  • Constipation. Your large intestine (colon) is responsible for absorbing water from your food. When you don’t have enough fluids, your stools may become harder and more difficult to pass.
  • Dry mouth, lips, or skin. As your body loses fluids, you may notice dryness, flaking, and cracking of your lips and skin.
  • Fatigue. Being dehydrated makes it harder for your body to carry out its normal functions. Because of this, you may feel lethargic or more tired than usual.
  • Headache. Headache due to dehydration is pretty common. A small 2004 study found that 1 in 10 study participants experienced headache due to dehydration. This was relieved by drinking water.

If you’re feeling dizzy due to dehydration, you can take the following steps to help ease your symptoms:

  • Rehydrate. Try to replenish lost fluids as soon as possible. Focus on drinking water. Sports drinks or oral rehydration solutions can also be helpful for restoring lost electrolytes.
  • Sit down. Move into a sitting position until your feelings of dizziness pass. When you begin to feel better, get up slowly.
  • Move slowly. Remember that dizziness and vertigo can increase your risk of falling. If you must move, do so slowly. Try to hold onto something in case you lose your balance.
  • Avoid certain activities. Some activities can be dangerous when you’re feeling dizzy. Avoid driving, operating machinery, or climbing up onto anything.

When to seek medical attention

There are some warning signs to watch out for that could be an indication that dehydration has become more serious. Seek immediate medical attention if you or a loved one:

Severe dehydration can cause serious complications, such as:

Dehydration can be treated in a hospital with intravenous (IV) fluids and electrolytes.

The following tips can help you stay hydrated throughout the day.

Get enough water

According to the Centers for Disease Control and Prevention (CDC), there are no specific recommendations on daily water intake.

However, according to the Mayo Clinic, drinking 8 glasses of water per day is a reasonable goal for most people.

Additionally, the National Academies of Sciences, Engineering, and Medicine notes that an adequate daily fluid intake is:

  • 2.7 liters (91 ounces) each day for women
  • 3.7 liters (125 ounces) each day for men

Your daily fluid intake doesn’t just include the water you drink but also fluids that you get from other foods and beverages, such as:

  • fruits with high water content like watermelon, strawberries, cantaloupe, and oranges
  • vegetables with high water content, such as lettuce, cabbage, and celery
  • low-sodium broths and soups
  • beverages like fat-free milk, herbal tea, juices, and sports drinks

Keep water on hand

Try to always have ready access to water. If you find that you often forget to hydrate, it may be helpful to make a habit of carrying a reusable water bottle with you.

Having water easily available is especially important when:

  • you’re exercising
  • the weather is hot or humid
  • you’re doing anything to make you sweat more than usual

Hydrate more when you’re ill

If you become sick with fever, vomiting, or diarrhea, be sure to drink additional fluids. Don’t wait until you’re already feeling dehydrated to have a drink of water.

There are other potential causes of vertigo. Many of these causes involve problems with your inner ear, which helps control your sense of balance. Inner ear conditions that can cause vertigo include:

Other conditions that can also cause vertigo include:

One of the potential symptoms of dehydration is dizziness. You may feel lightheaded or woozy. In some cases, you may also feel as if you or your surroundings are spinning or tilting. This is known as vertigo.

If you’re dehydrated and dizzy, try to drink fluids right away. Carefully move into a sitting position to avoid falling. When your dizziness passes, be sure to get up slowly.

You can prevent dehydration by taking in fluids throughout the day. You’ll need to hydrate more during exercise, in hot or humid weather conditions, and when you’re sick. If you or a loved one is severely dehydrated, be sure to get immediate medical care.