Hypertension vs Hypotension: What’s the Difference?

When it comes to blood pressure, you don’t want it to be too high or too low.

Both high blood pressure (hypertension) and low blood pressure (hypotension) can lead to serious health issues.

To help manage or prevent blood pressure complications, it’s important to monitor your health and get your blood pressure checked.

Additionally, understanding the differences between the two conditions is also crucial to preventing or treating them. 

In this article, I’ll discuss what blood pressure is  and the symptoms of hypotension and hypertension.

I’ll also explain the causes, risk factors, and treatments for both conditions.

Finally, I’ll explore how to check your blood pressure.

What Is Blood Pressure?

When your heart pumps blood through your arteries to other parts of your body, it pushes against the walls of your arteries.

This pressure is what’s known as blood pressure.  

Blood pressure is measured using two numbers: systolic blood pressure and diastolic blood pressure.

Systolic pressure is the first number, which measures how much pressure blood exerts against artery walls when your heart contracts, sending blood to the rest of the body.

Diastolic pressure measures how much pressure is in your arteries when your heart is at rest in between beats, filling with blood. 

According to the Centers for Disease Control and Prevention (CDC), normal blood pressure level for adults is less than 120 systolic and 80 diastolic, which would be written as 120/80 millimeters of mercury (mmHG) or said as 120 over 80. 

Hypertension reading 

High blood pressure, known as hypertension, is when your blood pressure is higher than normal.

While it may change throughout the day depending on what you’re doing, if your blood pressure continually measures above normal, you may be diagnosed with hypertension. 

There are two main types of high blood pressure:

• Stage 1 hypertension: When systolic blood pressure ranges from 130 to 139 mmHG or when diastolic blood pressure ranges from 80 to 89 mmHG.

• Stage 2 hypertension: When systolic blood pressure is higher than or equal to 140 mmHG or a diastolic pressure higher than or equal to 90 mmHG. This hypertension is more severe than stage 1. 

Hypotension reading 

Hypotension, or low blood pressure, is when your blood pressure is below 90/60 mmHG.

There are various categories of low blood pressure, which some of which include:

• Orthostatic or postural hypotension: This is when a sudden drop in blood pressure occurs when you go from sitting or lying down to standing up. For people with orthostatic hypotension, not enough blood that goes to their legs when standing due to gravity  returns to their brain. This can cause dizziness, blurred vision, lightheadedness, and fainting. 

• Postprandial hypotension: This happens when low blood pressure occurs one to two hours after eating. To digest a meal, the intestine needs more blood. When blood flows to the intestine, heart rate and speeds up and blood vessels constrict in other areas of the body to help maintain blood pressure. But for some people (typically older adults), these mechanisms don’t work properly, causing blood pressure to drop. This can cause dizziness, blurred vision, lightheadedness, and falls. 

• Neurally mediated hypotension: Mostly affecting children and young adults, this disorder causes blood pressure to drop after standing for long stretches of time. It may occur due to faulty brain communication between the brain and heart. 

Symptoms of Hypertension  

Most people who have high blood pressure don’t have signs or symptoms.

The only way to know if you have high blood pressure is to get your blood pressure checked by a healthcare professional.

However, severely high blood pressure can cause headaches, chest pain, or changes in vision.

Seek medical attention if you have high blood pressure and experience these symptoms. 

While high blood pressure typically does not cause symptoms, it can still lead to serious health issues that affect the heart, brain, kidneys, and eyes.

Having high blood pressure can decrease the flow of blood and oxygen to your heart and lead to heart disease.

The decreased blood flow can also cause chest pain, heart attacks, and heart failure.

High blood pressure can also cause a stroke by bursting or blocking arteries that carry blood and oxygen to the brain.

Additionally, high blood pressure can cause poorer cognitive function and even dementia.

It also raises your risk for kidney failure. 

Symptoms of Hypotension 

Symptoms of low blood pressure include:

• Fainting  
• Dizziness  
• Lightheadedness 
• Blurred vision  
• confusion
• Nausea or vomiting
• Lack of concentration
• Weakness
• Fatigue 

An extreme symptom of hypotension is shock, or sudden loss of blood.

It can lead to severe health conditions.

Seek medical help immediately if you experience these symptoms of shock:  confusion, clammy skin, weak and rapid pulse, or rapid and shallow breathing. 

Causes of Hypertension 

According to the U.S. Food & Drug Administration (FDA), high blood pressure affects more than 65 million adults.

High blood pressure can occur in an acute way based on what you’re doing.

It can be caused by stress, fatigue, pain, fear, or dehydration. 

However, if your blood pressure is frequently above normal, then you may be diagnosed with hypertension.

It typically happens over time from lifestyle choices and certain health conditions. 

Risk factors of hypertension   

Common risk factors of high blood pressure include:

• Elevated blood pressure between 120/80 mmHG and 129/80 mmHG
• Diabetes 
• Unhealthy diet that’s high in sodium and low in potassium
• Not enough physical activity 
• Obesity 
• Pregnancy 
• Too much alcohol 
• Tobacco use

Although anyone can have high blood pressure, some people have a higher chance of having it due to things they can’t control.

These risk factors include:

• Age: The older you get, the chance of having high blood pressure increases.

• Race: African Americans are at higher risk for high blood pressure.

• Gender: People born with vaginas are more likely to have high blood pressure after menopause, while people born with penises have a higher chance of having high blood pressure before the age of 55.

• Family history: Genetics may play a role in risk for high blood pressure.

Causes of Hypotension 

Blood pressure is typically the lowest at night, but it can lower throughout the day depending on what you’re doing, depending on various factors such as body position, time of day, stress level, and medications. 

Certain medical conditions can cause low blood pressure, including pregnancy, heart issues, dehydration, endocrine issues, diabetes, blood loss from injury or internal bleeding, severe allergic reaction, severe infection, lack of nutrients, particularly B-12, iron, and folate.

Low blood pressure may also be caused by medications and substances, such as alcohol, anti-anxiety medicine, antidepressants, heart medicines, painkillers, and diuretics. 

Risk factors of hypotension 

Although anyone can have hypotension, these risk factors increases chances of low blood pressure:

• Age: Orthostatic hypotension and postprandial hypotension typically occurs in adults above the age of 65. Neurally mediated hypotension is most common in children and young adults.

• Medication: People taking high blood pressure medications are at increased risk of low blood pressure

• Diseases: People with diabetes, Parkinson’s disease, and certain heart conditions may be at higher risk of having low blood pressure. 

Hypertension Treatment 

There are many FDA-approved medications for high blood pressure.

In addition to prescribing medication to lower your blood pressure, your healthcare professional may recommend managing hypertension by making lifestyle changes, including:

• Exercise at least 150 minutes a week 
• Don’t smoke
• Maintain a healthy weight
• Limit sodium and alcohol intake
• Eat a heart-healthy diet that includes vegetables, fruits, protein, dairy, oils, and grains
• Get enough sleep
• Manage stress

Hypotension Treatment  

If low blood pressure doesn’t cause symptoms or causes mild symptoms, it usually does not require treatment.

But if you have symptoms of hypotension, treatment depends on what’s causing them.

If medicines are causing low blood pressure, your doctor may adjust dosage or prescribe a different medication.

For low blood pressure caused by dehydration, drinking more water and adding electrolytes may be suggested by your doctor.  

Your doctor may suggest the following lifestyle changes to help reduce or prevent symptoms:

• Drink more water
• Limit alcohol intake
• Eat small meals that are low in carbohydrates
• Exercise regularly 
• Don’t sit with legs crossed

How to Check Your Blood Pressure  

Checking your blood pressure is fast and painless.

You can have your blood pressure measured at the doctor’s office, at a pharmacy with digital blood pressure machines, or at home.

No matter where you get it checked, the CDC recommends following these guidelines for the most accurate readings:

• Don’t eat or drink 30 minutes before taking your blood pressure
• Avoid tobacco, alcohol, and caffeine for at least 30 minutes prior to checking your blood pressure
• Make sure your bladder is empty before the reading
• Sit with your back supported, your feet flat on the floor, and your legs uncrossed
• Rest your arm at chest height
• Put the inflatable cuff on bare skin (not over clothing) and make sure it’s snug
• Don’t talk while you’re getting your blood pressure checked

So how does getting your blood pressure checked at the doctor’s office work?

The healthcare provider will wrap an inflatable cuff around your bare arm.

Then, they’ll inflate and tighten around your arm to momentarily stop the flow of blood in your artery.

There’s a gauge on the cuff that will measure the pressure in your blood vessels.

While the healthcare professional is letting air out of the cuff slowly, they’ll listen to your pulse and look at the gauge.

If the device is digital, then the healthcare professional will not use a stethoscope.  

If you have high blood pressure, your healthcare professional may recommend regularly checking your blood pressure at home with a personal blood pressure measurement device.

If you regularly self-measure your blood pressure at home, be sure to keep a log of your measurements, take your blood pressure at the same time every day, and take at least two readings.

If you have questions or concerns about your blood pressure, K Health can help. Did you know you can get affordable primary care with the K Health app?

Download K Health to check your symptoms, explore conditions and treatments, and, if needed, text with a clinician in minutes. K Health’s AI-powered app is based on 20 years of clinical data.