Hypertension results from a complex interaction of genes and environmental factors. Numerous common genetic variants with small effects on blood pressure have been identified[34] as well as some rare genetic variants with large effects on blood pressure.[35] Also, genome-wide association studies (GWAS) have identified 35 genetic loci related to blood pressure; 12 of these genetic loci influencing blood pressure were newly found.[36] Sentinel SNP for each new genetic locus identified has shown an association with DNA methylation at multiple nearby CpG sites. These sentinel SNP are located within genes related to vascular smooth muscle and renal function. DNA methylation might affect in some way linking common genetic variation to multiple phenotypes even though mechanisms underlying these associations are not understood. Single variant test performed in this study for the 35 sentinel SNP (known and new) showed that genetic variants singly or in aggregate contribute to risk of clinical phenotypes related to high blood pressure.[36]

Hypertension results from a complex interaction of genes and environmental factors. Numerous common genetic variants with small effects on blood pressure have been identified[34] as well as some rare genetic variants with large effects on blood pressure.[35] Also, genome-wide association studies (GWAS) have identified 35 genetic loci related to blood pressure; 12 of these genetic loci influencing blood pressure were newly found.[36] Sentinel SNP for each new genetic locus identified has shown an association with DNA methylation at multiple nearby CpG sites. These sentinel SNP are located within genes related to vascular smooth muscle and renal function. DNA methylation might affect in some way linking common genetic variation to multiple phenotypes even though mechanisms underlying these associations are not understood. Single variant test performed in this study for the 35 sentinel SNP (known and new) showed that genetic variants singly or in aggregate contribute to risk of clinical phenotypes related to high blood pressure.[36]


The NHLBI is part of the U.S. Department of Health and Human Services’ National Institutes of Health (NIH)—the Nation’s biomedical research agency that makes important scientific discovery to improve health and save lives. We are committed to advancing science and translating discoveries into clinical practice to promote the prevention and treatment of heart, lung, blood, and sleep disorders, including high blood pressure. Learn about the current and future NHLBI efforts to improve health through research and scientific discovery.
As blood travels throughout your body, it presses against the walls of your blood vessels, just like water in a hose or air in a tire. This is called blood pressure. When your heart beats (contracts), squeezing blood out and pumping it into your arteries, blood pressure peaks. This is called your systolic pressure. Between heartbeats, when your heart relaxes and blood flows back into it, your blood pressure is lower. This is your diastolic pressure.

Unlike high blood pressure, low blood pressure is defined primarily by signs and symptoms of low blood flow and not by a specific blood pressure number. Some individuals routinely may have blood pressure numbers of 90/50 with no symptoms and therefore do not have low blood pressure. However, others who normally have higher blood pressures may develop symptoms of low blood pressure if their blood pressure drops to 100/60.
Sodium is a key part of how the body controls blood pressure levels. The kidneys help balance fluid and sodium levels in the body. They use sodium and potassium to remove excess fluid from the blood. The body gets rid of this excess fluid as urine. When sodium levels in the blood are high, blood vessels retain more fluid. This increases blood pressure against the blood vessel walls.
Right after exercise is stopped, blood pressure decreases — often to levels a bit lower than normal resting blood pressure, and this effect can last for hours. Also, people who exercise regularly usually experience permanent improvements in resting blood pressure levels, as exercise strengthens the heart, helps with weight loss, improves circulation and lessens peripheral resistance — all factors that benefit blood pressure.
Even occasional dizziness or lightheadedness may be a relatively minor problem — the result of mild dehydration from too much time in the sun or a hot tub, for example. Still, it's important to see your doctor if you have signs or symptoms of hypotension because they can point to more-serious problems. It can be helpful to keep a record of your symptoms, when they occur and what you're doing at the time.
^ Ostchega Y, Dillon CF, Hughes JP, Carroll M, Yoon S (July 2007). "Trends in hypertension prevalence, awareness, treatment, and control in older U.S. adults: data from the National Health and Nutrition Examination Survey 1988 to 2004". Journal of the American Geriatrics Society. 55 (7): 1056–65. doi:10.1111/j.1532-5415.2007.01215.x. PMID 17608879.
To make an official diagnosis of high blood pressure you will need to see your doctor. Often your blood pressure will be checked on at least two different visits, at different times of the day. Your doctor may ask you to keep a blood pressure log for a short time in order to see your overall blood pressure trends. If your blood pressure is consistently over 134/80, your doctor will work with you to determine the best regimen for treating your high blood pressure.
One especially important cause of low blood pressure is orthostatic hypotension, which is sometimes referred to as postural hypotension. This happens when blood pressure drops rapidly during changes in body position—usually when changing from sitting to standing—inducing classic signs that the blood pressure is too low, like dizziness, blurry vision, and fainting.
Many things can cause your blood pressure to be too low, ranging from normal pregnancy-induced changes to dangerous underlying conditions, like heart problems or hormone disturbances. In some instances, what causes low blood pressure could be a simple case of dehydration brought on by vomiting, intense exercise, or the overuse of diuretics. In fact, even mild dehydration can trigger symptoms such as dizziness, confusion, or other symptoms of low blood pressure.

For a manual monitor, you have to hold the pressure gauge in one hand (your weaker hand) and the bulb in the other hand. Inflate the cuff until it reads about 30 points above your normal systolic pressure. At this point, you should not hear your pulse in the stethoscope. When you hear the first heart beat, this is the systolic pressure. As you deflate the cuff, keep listening for a heart beat. When you can no longer hear it, that is your diastolic pressure.

The new guidelines also encourage additional monitoring, using a wearable digital monitor that continually takes blood pressure readings as you go about your life, or checked with your own cuff at home. This additional monitoring can help to tease out masked hypertension (when the blood pressure is normal in our office, but high the rest of the time) or white coat hypertension (when the blood pressure is high in our office, but normal the rest of the time). There are clear, helpful directions for setting patients up with a home blood pressure monitor, including a recommendation to give people specific instructions on when not to check blood pressure (within 30 minutes of smoking, drinking coffee, or exercising) and how to take a measurement correctly (seated comfortably, using the correct size cuff). The home blood pressure cuff should first be validated (checked in the office, for accuracy).
^ Martin-Cabezas, Rodrigo; Seelam, Narendra; Petit, Catherine; Agossa, Kévimy; Gaertner, Sébastien; Tenenbaum, Henri; Davideau, Jean-Luc; Huck, Olivier (October 2016). "Association between periodontitis and arterial hypertension: A systematic review and meta-analysis". American Heart Journal. 180: 98–112. doi:10.1016/j.ahj.2016.07.018. ISSN 1097-6744. PMID 27659888.
An exception to this is those with very high blood pressure readings especially when there is poor organ function.[79] Initial assessment of the hypertensive people should include a complete history and physical examination. With the availability of 24-hour ambulatory blood pressure monitors and home blood pressure machines, the importance of not wrongly diagnosing those who have white coat hypertension has led to a change in protocols. In the United Kingdom, current best practice is to follow up a single raised clinic reading with ambulatory measurement, or less ideally with home blood pressure monitoring over the course of 7 days.[79] The United States Preventive Services Task Force also recommends getting measurements outside of the healthcare environment.[80] Pseudohypertension in the elderly or noncompressibility artery syndrome may also require consideration. This condition is believed to be due to calcification of the arteries resulting in abnormally high blood pressure readings with a blood pressure cuff while intra arterial measurements of blood pressure are normal.[81] Orthostatic hypertension is when blood pressure increases upon standing.[82]
Wear a blood pressure monitor. This monitor is attached to you. You will be asked to wear it for 24 hours. The monitor is usually programmed to take blood pressure readings every 15 to 30 minutes all day and night while you go about your normal activities. The doctor will evaluate the results. In some cases, home blood pressure monitors may also be used to evaluate the effectiveness of your treatment.

However, sometimes a high reading can occur temporarily and then your numbers will return to normal. If your blood pressure measures at this level, your doctor will likely take a second reading after a few minutes have passed. A second high reading indicates that you’ll need treatment either as soon as possible or immediately depending on whether or not you have any of the symptoms described above.

Normal blood pressure is less than 120/80. Knowing your blood pressure and remembering to check it regularly can help save your life. Choosing healthier, heart-conscious foods, maintaining a healthy weight, getting up and staying active, and managing your stress are great ways to help keep your blood pressure at the level it should be. Learn more about what you can do to help control your blood pressure.


How can I stabilize my blood pressure? A wide range of factors influences blood pressure, including anxiety, stress, and medications. High blood pressure can have severe complications, such as a heart attack or stroke. A person can address fluctuating blood pressure with home remedies and lifestyle changes. Learn more about normalizing blood pressure here. Read now

Why stress happens and how to manage it Stress is essential for survival; the chemicals it triggers help the body prepare to face danger and cope with difficulty. Long-term stress is linked to various health conditions and can cause physical and psychological symptoms. How is it diagnosed, what types of stress are there, and how is it treated or managed? Read now
This study will assess whether minocycline, an antibiotic with anti-inflammatory effects, can improve blood pressure control in patients who do not respond to medicines in combination with lifestyle changes, such as physical activity, weight loss, and healthy eating patterns. To participate you must be at least 18 years old and have high blood pressure that does not respond to treatment with three different high blood pressure medicines even when used at the maximum doses. Please note that this study is in Gainesville, Florida.
Hypertension defined as elevated blood pressure over several visits affects 1% to 5% of children and adolescents and is associated with long term risks of ill-health.[89] Blood pressure rises with age in childhood and, in children, hypertension is defined as an average systolic or diastolic blood pressure on three or more occasions equal or higher than the 95th percentile appropriate for the sex, age and height of the child. High blood pressure must be confirmed on repeated visits however before characterizing a child as having hypertension.[89] Prehypertension in children has been defined as average systolic or diastolic blood pressure that is greater than or equal to the 90th percentile, but less than the 95th percentile.[89] In adolescents, it has been proposed that hypertension and pre-hypertension are diagnosed and classified using the same criteria as in adults.[89]

The American Heart Association, or AHA, explains that the early symptoms of high blood pressure that people tend to think about are largely mythical. You are unlikely to notice “classic” signs such as anxiety, insomnia, or flushing in your face. You could have blood spots in your eyes due to subconjunctival hemorrhage, but dizziness itself is not among the essential symptoms of high blood pressure.
One reason to visit your doctor regularly is to have your blood pressure checked. Routine checks of your blood pressure will help pick up an early rise in blood pressure, even though you might feel fine. If there's an indication that your blood pressure is high at two or more checkups, the doctor may ask you to check your blood pressure at home at different times of the day. If the pressure stays high, even when you are relaxed, the doctor may suggest exercise, changes in your diet, and, most likely, medications.
A blood pressure reading contains two numbers: systolic pressure and diastolic pressure. Systolic pressure is the top or first number in your blood pressure reading; it indicates the pressure within your arteries when your heart pumps out blood. Diastolic pressure is the bottom number, and shows the pressure in your arteries while your heart is filling with blood.
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for general informational purposes only and does not address individual circumstances. It is not a substitute for professional medical advice, diagnosis or treatment and should not be relied on to make decisions about your health. Never ignore professional medical advice in seeking treatment because of something you have read on the WebMD Site. If you think you may have a medical emergency, immediately call your doctor or dial 911.

One reason to visit your doctor regularly is to have your blood pressure checked. Routine checks of your blood pressure will help pick up an early rise in blood pressure, even though you might feel fine. If there's an indication that your blood pressure is high at two or more checkups, the doctor may ask you to check your blood pressure at home at different times of the day. If the pressure stays high, even when you are relaxed, the doctor may suggest exercise, changes in your diet, and, most likely, medications.
NHLBI Expert Panel on Cardiovascular Health and Risk Reduction in Children and Adolescents. We have supported the development of guidelines based on up-to-date research to evaluate and manage risk of heart disease in children and adolescents, including high blood pressure. Visit Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents for more information.
Anyone can develop hypotension, but certain groups of people are more likely to experience it, and there are different types. For instance, orthostatic (positional) hypotension, which occurs when you stand up after sitting or lying down, is more common in older adults. Typically, “your body has certain compensatory mechanisms to prevent your blood pressure from falling when you stand up,” explains Willie Lawrence, MD, an interventional cardiologist at Research Medical Center in Kansas City, Missouri, and a spokesperson for the American Heart Association. But, he adds, “orthostatic hypotension is a problem for some people because these reflexes that should occur, don’t occur.”
Electrocardiogram (ECG): This tests the heart's electrical activity. This test is more commonly used for patients at high risk of heart problems, such as hypertension and elevated cholesterol levels. The initial ECG is called a baseline. Subsequent ECGs may be compared with the baseline to reveal changes which may point to coronary artery disease or thickening of the heart wall.
Vasovagal syncope can be treated with several types of drugs such as beta blockers, for example, propanolol (Inderal, Inderal LA) and selective serotonin reuptake inhibitors such as fluoxetine (Prozac), escitalopram oxalate (Lexapro), paroxetine (Paxil), sertraline (Zoloft), citalopram (Celexa), and fluvoxamine (Luvox). Fludrocortisone (Florinef) (a drug that prevents dehydration by causing the kidney(s) to retain water) also may be used. A pacemaker can also be helpful when a patient fails drug therapy.
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