Commitment + Clinical Leadership = Better Outcomes

The Link Between Dehydration and Blood Pressure

The Link Between Dehydration and Blood Pressure

Apr. 27th, 2023

Staying hydrated and having a healthy blood pressure are both essential to your wellbeing. Water is needed for many functions in your body, and your blood pressure is key to keeping your blood flowing so it can deliver oxygen and nutrients throughout your whole body.

Drinking plenty of fluids to stay hydrated is a simple way to ensure your blood pressure remains stable. When you’re dehydrated, your blood pressure can either sky rocket or plummet, both of which can be dangerous. In severe cases, this major fluctuation can send you into a state of shock.

Here are some signs you may be dehydrated, as well as how dehydration and blood pressure are connected.

What Does it Mean to Be Dehydrated?

Many people live daily without realizing they’re dehydrated. In fact, it’s estimated that 75% of Americans are dehydrated. Water is critical to the body and its daily functions. Water delivers oxygen to organs, aids in digestion, and balances your body’s temperature.1

Dehydration is the lack of water throughout the body, especially in the blood vessels and cells. Simply put, dehydration means you’re losing more water than you’re taking in.2

Dehydration can affect anyone at any age. Here are some of the common causes of dehydration:

  • Not drinking enough fluids
  • Sweating
  • Vomiting
  • Fever
  • Increased urination
  • Chronic illnesses

Symptoms of dehydration can range from mild to severe. Pay close attention if you experience any of the following symptoms of dehydration:

  • Dry mouth
  • Muscle weakness
  • Headache
  • Dizziness
  • Lack of energy
  • Dry skin

If you have concerns about yourself or a loved one becoming easily dehydrated or experiencing it often, talk with a medical professional.

How Does Dehydration Affect Blood Pressure?

Did you know that approximately 60% of your body is made of water? Even more importantly, 90% of your blood is water.3

Blood pressure is the force your blood exerts on the walls of the arteries and veins. And since your blood needs water, dehydration can cause you to experience fluctuations in your blood pressure.

A normal blood pressure is less than 120/80 mm Hg. It’s completely natural for your blood pressure to rise and fall throughout the day. However, your doctor can help you determine if you have ongoing low or high blood pressure, and what could potentially be causing it.4

Does Dehydration Cause Low Blood Pressure?

When you become dehydrated, your body is depleted of the water it needs throughout the body, which includes blood. Without sufficient water in your system, you will have low blood volume, which will result in low blood pressure. Low blood pressure is typically below 90/60 mm Hg.

When you experience low blood pressure, your organs may not receive the oxygen needed to function. An extreme drop in blood pressure can cause heart or brain damage.

Signs of low blood pressure include:

  • Feeling lightheaded
  • Dizziness
  • Nausea
  • Blurred vision
  • Fast breathing
  • Fatigue
  • Feeling weak
  • Confusion

If you experience any signs of low blood pressure, talk with your doctor.3

Does Dehydration Cause High Blood Pressure?

Dehydration can also lead to high blood pressure. High blood pressure is typically any number reading above 140/90 mm Hg.

Dehydration may increase your blood pressure due to an anti-diuretic hormone called vasopressin. Blood volume naturally decreases when you become dehydrated. When your body senses a change in blood volume, higher amounts of vasopressin are released and secreted. High levels of vasopressin cause your blood vessels to constrict, leading to high blood pressure.5

A study found that frequent dehydration can lead to changes in blood vessel function and blood vessel regulation.6 Over time, these changes can lead to hypertension, also known as high blood pressure.7

Many people who have high blood pressure may not be aware since it typically doesn’t show any symptoms. On the occasion that high blood pressure shows symptoms after an extended period of time, some common signs include8:

  • Headaches
  • Shortness of breath
  • Bloody nose

Tips to Avoid Dehydration and Fluctuating Blood Pressure Levels

There are many ways you can live a healthy lifestyle and avoid dehydration, as well as potential health concerns such as fluctuating blood pressure.

  • Drink water. If you struggle to drink enough water, try adding fruit to make it more flavorful or carry a water bottle around with you to encourage you to drink more throughout the day.
  • Compensate for the water you lose. If you are active, sweat a lot, or are out in the heat, make sure to replenish your body with water since you’re constantly losing it when you sweat.
  • Replenish electrolytes. Electrolytes are responsible for maintaining fluid levels in the body and directing water and nutrients to parts of the body where it is needed. When you lose water, you’re losing essential electrolytes as well.9
  • Limit fluids that dehydrate you. There are certain diuretics, including coffee, tea, and alcohol, that can cause you to lose more fluid. Try to limit these drinks to decrease your risk of dehydration.
  • Prepare ahead of time. If you’re traveling or will be in an area where clean drinking water is not readily available, make sure to prepare beforehand and have water bottles with you.
  • Visit your doctor. It’s important to see your doctor annually, especially if you’re at high risk for dehydration or blood pressure fluctuations. Your doctor will check your blood pressure and help you come up with a treatment plan.

Keep in mind that dehydration is only one potential cause of high blood pressure. High blood pressure can also be caused by other medical conditions and lifestyle behaviors. If you or a loved one believe you’re at risk, talk with your doctor.

About Saber Healthcare Group

Saber Healthcare is an organization that provides services to more than 115 buildings across the states of Ohio, Pennsylvania, Virginia, North Carolina, Indiana, Delaware, and Florida. To learn more about our company and services, click here.

Saber Healthcare is an organization dedicated to providing consultant services to long-term care providers. This article is for informational purposes and is not meant to be seen as professional advice. Please consult with a medical expert before relying on the information provided.


  1. “Adult Dehydration.” National Library of Medicine, Accessed March 29th, 2023.,frequent%20cause%20of%20hospital%20admission.
  2. “Dehydration: What Causes It and How To Avoid It.” Saber Healthcare Group, July 29th, 2022. Accessed March 29th, 2023.
  3. “The Link Between Dehydration and Blood Pressure.” Cleveland Clinic, February 2nd, 2023. Accessed March 29th, 2023.
  4. “High Blood Pressure Symptoms and Causes.” U.S. Department of Health & Human Services, Centers for Disease Control and Prevention. Accessed March 30th, 2023.,pressure%20in%20a%20healthy%20range.
  5. Biggers, Alana. “Can Dehydration Affect Your Blood Pressure?” Healthline Media, January 15th, 2020. Accessed March 29th, 2023.
  6. “Hydration Status and Cardiovascular Function.” National Library of Medicine, PubMed Central. Accessed March 30th, 2023.
  7. Williams, Carolyn. “Does Dehydration Cause High Blood Pressure?” Dotdash Meredith, February 4th, 2023. Accessed March 30th, 2023.
  8. “Can Dehydration Cause High Blood Pressure?” Healthcare Associates of Texas, December 21st, 2021. Accessed March 29th, 2023.
  9. “Water + Electrolytes: How They Prevent Dehydration.” Elete – The Electrolyte Concentrate, Accessed March 29th, 2023.,fluid%20balance%20inside%20the%20cells.