Know your numbers
Your doctor just told you that your blood pressure is higher than it should be—but you feel fine. What gives?

With high blood pressure, the force of blood flowing through your blood vessels is consistently too high. But it doesn't usually cause any symptoms. That's why many people who are walking around with high blood pressure (aka, hypertension) don't know they have it.

High blood pressure can develop slowly over time. When left undiagnosed and untreated, it can increase your risk for heart attack and stroke, which is why it is known as a silent killer.

The only way to know if you have high blood pressure is to have your blood pressure measured. Your healthcare provider can take it by placing a blood pressure cuff on your arm during an office visit, or you can measure your own pressure at home. (More on that later, but here are at-home blood pressure monitors you can buy on Amazon.)

A blood pressure reading is given as two numbers. For instance, blood pressure numbers of less than 120/80 mm Hg are considered within the normal range.

Your systolic blood pressure, the upper number, refers to how much pressure your blood is exerting against your artery walls when your heart beats. Diastolic blood pressure, the lower number, indicates how much pressure your blood is exerting against your artery walls when your heart is resting between beats.

High blood pressure is usually diagnosed in stages. Elevated blood pressure is a systolic pressure of 120-129 mm Hg, and a diastolic pressure of less than 80 mm Hg. High blood pressure Stage 1 is defined as 130-139 over 80-89 mm Hg.

What does high blood pressure feel like?
High blood pressure doesn't typically feel like much of anything, says Vijay Nambi, MD, associate professor of medicine at Baylor College of Medicine in Houston.

"We don't want to say there are these symptoms of high blood pressure because then people may say, 'I don't have high blood pressure' when most people are not symptomatic." (These are the health dangers of even slightly high blood pressure.)

How do you feel when you have high blood pressure?
There are always outliers with high blood pressure who will experience high blood pressure headaches, fatigue, dizziness, nosebleeds, or other symptoms.

The American Heart Association (AHA) notes that blood spots in the eyes and facial flushing are also among the symptoms. Neither of these are caused by high blood pressure per se. For example, facial flushing, which occurs when blood vessels in the face expand, may occur with stress, alcohol consumption, and exercise—all of which can raise blood pressure temporarily.

Symptoms can be the chicken or the egg, Dr. Nambi explains. "You may have head pain and as a result, your blood pressure climbs, or your blood pressure may cause the pain." If you are taking medication to control your blood pressure, it could be the cause of symptoms, as well.

It's not always easy to figure out what is happening and why, Dr. Nambi says.

High blood pressure emergency symptoms
Headaches and nosebleeds can be symptoms of a hypertensive emergency or crisis. If your blood pressure is 180/120 mm Hg or higher and you have these symptoms—along with chest pain, back pain, numbness or weakness, or a change in vision—you should seek care right away.

"Call 911 or get to the nearest emergency room," Dr. Nambi says.

High blood pressure diagnosis
In the absence of any symptoms, the only way to tell if your blood pressure is too high is to know your numbers. Your doctor will take your blood pressure during your well visits, but taking it at home will also give you an idea of where you stand.

Technique matters when you measure your own blood pressure, Dr. Nambi says.

"Take it in a quiet spot with your feet on the ground and make sure to use the correct cuff size." Take two readings and use the average of both. "Getting a home blood pressure monitor is helpful as some people are nervous when they see a doctor and will develop white coat hypertension," he adds. White coat hypertension is a situation in which blood pressure can climb in a doctor's office—possibly just from the stress of having it taken—but an individual doesn't have high blood pressure at other times.

Don't take your blood pressure when drinking coffee, watching the news, or doing anything that is overly stimulating or stressful as that can skew the results, he says.

High blood pressure treatment
Depending on how high your numbers are and whether you have any other risk factors for heart disease or stroke, your doctor will likely suggest lifestyle changes with or without blood pressure-lowering medications.

Eat a heart-healthy diet
These changes include eating a heart-healthy low-salt diet such as the DASH diet—short, for Dietary Approaches to Stop Hypertension—or the Mediterranean diet, which is rich in healthy fats, whole grains, lean proteins, fruits, and vegetables.

Exercise regularly
Aerobic activity such as brisk walking, jogging, or using an elliptical trainer is the best exercise for lowering your blood pressure. The AHA suggests aiming for at least 150 minutes of moderate aerobic physical activity a week.

Quit smoking and limit drinking
Quitting smoking and limiting alcohol consumption to no more than two drinks a day for men or one drink a day for women can also make a difference in your blood pressure.

Practice mindfulness
Finding a way to take the edge off of stress—whether it's mindfulness, meditation, or deep breathing—and doing it every day, can also lower blood pressure over the long term.

In a study, published in 2019 in PLOS One, people with high blood pressure who participated in 10 mindfulness sessions in which they learned to focus on the present moment showed reductions in blood pressure even one year after the study. Those who had the highest blood pressure when the study began saw the greatest benefits.

Take your medication
You may still need medication to get your blood pressure back into the healthy range, says Salim Virani, MD, cardiologist at the Michael E. DeBakey Veterans Affairs Medical Center, in Houston.

"Don't wait for symptoms to take your blood pressure medication," he cautions. "Blood pressure-lowering medication must be taken on a regular basis regardless of symptoms." (Also, try these natural remedies for high blood pressure.)

The last word
If your blood pressure is high, you are in the driver's seat and have a head start on heart attack, stroke, and other complications. Don't wait for symptoms to get tested because high blood pressure doesn't usually cause any.

If you have extremely high blood pressure and experience headache, nose bleed, or other symptoms that are accompanied by chest pain and numbness, it is a medical emergency.