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.

If your blood pressure is 120/80 millimeters of mercury (mm Hg) or lower, it’s considered normal. Generally, if the blood pressure reading is under 90/60 mm Hg, it is abnormally low and is referred to as hypotension. Some adults regularly have a blood pressure in the hypotensive range, but have no symptoms at all and do not require treatment. In serious cases, though, hypotension can result in a decreased supply of oxygen and nutrients to your brain, which can eventually lead to life-threatening shock.


Hypertension clinical guidelines from the American Heart Association are comprehensive guidelines for healthcare professionals for the detection and treatment of high blood pressure in a wide range of patients. Included in the 2018 hypertension clinical guidelines are proper methods for measuring blood pressure, risk factors for hypertension, and hypertension treatment for different populations.
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Methyldopa, formerly known under the brand name Aldomet, is one of the oldest blood pressure medications still in use. It was first introduced more than 50 years ago. Methyldopa works in the central nervous system to lower blood pressure. While its general use has declined over the years, methyldopa is considered the first-line of treatment for high blood pressure that develops during pregnancy.

^ Mente, Andrew; O'Donnell, Martin; Rangarajan, Sumathy; Dagenais, Gilles; Lear, Scott; McQueen, Matthew; Diaz, Rafael; Avezum, Alvaro; Lopez-Jaramillo, Patricio; Lanas, Fernando; Li, Wei; Lu, Yin; Yi, Sun; Rensheng, Lei; Iqbal, Romaina; Mony, Prem; Yusuf, Rita; Yusoff, Khalid; Szuba, Andrzej; Oguz, Aytekin; Rosengren, Annika; Bahonar, Ahmad; Yusufali, Afzalhussein; Schutte, Aletta Elisabeth; Chifamba, Jephat; Mann, Johannes F E; Anand, Sonia S; Teo, Koon; Yusuf, S (July 2016). "Associations of urinary sodium excretion with cardiovascular events in individuals with and without hypertension: a pooled analysis of data from four studies". The Lancet. 388 (10043): 465–75. doi:10.1016/S0140-6736(16)30467-6. PMID 27216139.
"Having a healthy lifestyle really makes a difference in your life because you can avoid high blood pressure," said Dr. Mary Ann Bauman, an internist at Integris Baptist Medical Center in Oklahoma City. "If you do have high blood pressure, make sure take your medication. You may not necessarily have symptoms until your blood pressure gets really high."
Hypertension is high blood pressure, a very common condition in older adults. Blood pressure is the physical force exerted by the blood as it pushes against the walls of the arteries. Blood pressure readings are written in two numbers separated by a line. The top number represents the systolic blood pressure and the bottom number represents the diastolic pressure. The systolic blood pressure is the pressure in the arteries as the heart contracts pushing the blood forward. The diastolic pressure is the pressure in the arteries as the heart relaxes.
However, the guidelines stress that, for most of the newly classified patients, the recommended treatment will be lifestyle modifications, such as weight loss and changes in diet and exercise levels, as opposed to medications. Only a small increase in the percentage of U.S. adults receiving blood pressure medications — about 2 percent — is expected, the authors said.
It is important to recognise that low blood pressure can cause no symptoms at all, and is a common normal finding in young people and athletes. However, in some people, low blood pressure causes symptoms which can significantly interfere with their quality of life. These can include syncope (fainting), pre-syncope (near fainting, usually associated with feeling light-headed), sweating, tiredness, slow thinking (brain fog), nausea, visual blurring, hearing disturbances, headache, palpitations, neck pain, breathlessness and chest pain.
^ 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.
It has been shown that meditation and other relaxation techniques can help lower blood pressure. Yoga, tai chi, and breathing exercises can also help reduce blood pressure. It's best when these are combined with changes in diet and exercise. Tell your doctor if you are taking any herbal remedies, since some of these preparations can actually raise blood pressure or interact with your blood pressure medications. The following are supplements that may lower blood pressure:

The kidney can respond to changes in blood pressure by increasing or decreasing the amount of urine that is produced. Urine is primarily water that is removed from the blood. When the kidney makes more urine, the amount (volume) of blood that fills the arteries and veins decreases, and this lowers blood pressure. If the kidneys make less urine, the amount of blood that fills the arteries and veins increases and this increases blood pressure. Compared with the other mechanisms for adjusting blood pressure, changes in the production of urine affect blood pressure slowly over hours and days. (The other mechanisms are effective in seconds.)

Understanding the normal BP range with age can help the doctor and you to estimate your cardiovascular health. Blood pressure levels can fluctuate significantly from one reading to the next and it is important to remember that just one abnormally high reading does not signify that you have high blood pressure. Doctors usually use an average of multiple blood pressure readings taken over a period of several days to arrive at a diagnosis of high blood pressure.

^ Aronow WS, Fleg JL, Pepine CJ, Artinian NT, Bakris G, Brown AS, Ferdinand KC, Ann Forciea M, Frishman WH, Jaigobin C, Kostis JB, Mancia G, Oparil S, Ortiz E, Reisin E, Rich MW, Schocken DD, Weber MA, Wesley DJ, Harrington RA, Bates ER, Bhatt DL, Bridges CR, Eisenberg MJ, Ferrari VA, Fisher JD, Gardner TJ, Gentile F, Gilson MF, Hlatky MA, Jacobs AK, Kaul S, Moliterno DJ, Mukherjee D, Rosenson RS, Stein JH, Weitz HH, Wesley DJ (2011). "ACCF/AHA 2011 expert consensus document on hypertension in the elderly: a report of the American College of Cardiology Foundation Task Force on Clinical Expert Consensus Documents developed in collaboration with the American Academy of Neurology, American Geriatrics Society, American Society for Preventive Cardiology, American Society of Hypertension, American Society of Nephrology, Association of Black Cardiologists, and European Society of Hypertension". J Am Soc Hypertens. 5 (4): 259–352. doi:10.1016/j.jash.2011.06.001. PMID 21771565.
Once the diagnosis of hypertension has been made, healthcare providers should attempt to identify the underlying cause based on risk factors and other symptoms, if present. Secondary hypertension is more common in preadolescent children, with most cases caused by kidney disease. Primary or essential hypertension is more common in adolescents and has multiple risk factors, including obesity and a family history of hypertension.[83] Laboratory tests can also be performed to identify possible causes of secondary hypertension, and to determine whether hypertension has caused damage to the heart, eyes, and kidneys. Additional tests for diabetes and high cholesterol levels are usually performed because these conditions are additional risk factors for the development of heart disease and may require treatment.[6]

Stress reduction techniques such as biofeedback or transcendental meditation may be considered as an add-on to other treatments to reduce hypertension, but do not have evidence for preventing cardiovascular disease on their own.[125][126][127] Self-monitoring and appointment reminders might support the use of other strategies to improve blood pressure control, but need further evaluation.[128]

It is important to recognise that low blood pressure can cause no symptoms at all, and is a common normal finding in young people and athletes. However, in some people, low blood pressure causes symptoms which can significantly interfere with their quality of life. These can include syncope (fainting), pre-syncope (near fainting, usually associated with feeling light-headed), sweating, tiredness, slow thinking (brain fog), nausea, visual blurring, hearing disturbances, headache, palpitations, neck pain, breathlessness and chest pain.


Low blood pressure is also known as hypotension. This is usually defined in an adult as a systolic recording of less than 90 mmHg, although it has been suggested that for elderly people, below 110 mmHg is a more appropriate definition. Blood pressure and heart rate are controlled by the autonomic nervous system (the nervous system that controls bodily functions that we do not have to think about).                                                                                                                                                                                                
Blood pressure readings fall into four general categories, ranging from normal to stage 2 high blood pressure (hypertension). The level of your blood pressure determines what kind of treatment you may need. To get an accurate blood pressure measurement, your doctor should evaluate your readings based on the average of two or more blood pressure readings at three or more office visits.
Most doctors do not make a final diagnosis of high blood pressure until they measure your blood pressure several times (at least 2 blood pressure readings on 3 different days). Some doctors ask their patients to wear a portable machine that measures their blood pressure over the course of several days. This machine may help the doctor find out whether a patient has true high blood pressure or what is known as “white-coat hypertension.” White-coat hypertension is a condition in which a patient’s blood pressure rises during a visit to a doctor when anxiety and stress probably play a role.
Blood pressure rises with aging and the risk of becoming hypertensive in later life is considerable.[37] Several environmental factors influence blood pressure. High salt intake raises the blood pressure in salt sensitive individuals; lack of exercise, obesity, and depression[38] can play a role in individual cases. The possible roles of other factors such as caffeine consumption,[39] and vitamin D deficiency[40] are less clear. Insulin resistance, which is common in obesity and is a component of syndrome X (or the metabolic syndrome), is also thought to contribute to hypertension.[41] One review suggests that sugar may play an important role in hypertension and salt is just an innocent bystander.[42]
Dehydration can sometimes cause blood pressure to drop. However, dehydration does not always cause low blood pressure. Fever, vomiting, severe diarrhea, overuse of diuretics and strenuous exercise can all lead to dehydration, a potentially serious condition in which your body loses more water than you take in. Even mild dehydration (a loss of as little as 1 percent to 2 percent of body weight) can cause weakness, dizziness and fatigue.

^ Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents, National Heart, Lung, and Blood Institute (Dec 2011). "Expert panel on integrated guidelines for cardiovascular health and risk reduction in children and adolescents: summary report". Pediatrics. 128 Suppl 5: S213–56. doi:10.1542/peds.2009-2107C. PMC 4536582. PMID 22084329.
Blood pressure refers to the force exerted by circulating blood on the walls of blood vessels and constitutes one of the principal vital signs. The pressure of the circulating blood decreases as blood moves through arteries, arterioles, capillaries, and veins; the term blood pressure generally refers to arterial pressure, i.e., the pressure in the larger arteries, arteries being the blood vessels which take blood away from the heart.

Understanding the normal BP range with age can help the doctor and you to estimate your cardiovascular health. Blood pressure levels can fluctuate significantly from one reading to the next and it is important to remember that just one abnormally high reading does not signify that you have high blood pressure. Doctors usually use an average of multiple blood pressure readings taken over a period of several days to arrive at a diagnosis of high blood pressure.
^ Jump up to: a b Acierno, Mark J.; Brown, Scott; Coleman, Amanda E.; Jepson, Rosanne E.; Papich, Mark; Stepien, Rebecca L.; Syme, Harriet M. (2018-10-24). "ACVIM consensus statement: Guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats". Journal of Veterinary Internal Medicine. 32 (6): 1803–1822. doi:10.1111/jvim.15331. ISSN 1939-1676. PMC 6271319. PMID 30353952.

A sudden fall in blood pressure can be dangerous. A change of just 20 mm Hg — a drop from 110 systolic to 90 mm Hg systolic, for example — can cause dizziness and fainting when the brain fails to receive an adequate supply of blood. And big plunges, such as those caused by uncontrolled bleeding, severe infections or allergic reactions, can be life-threatening.
To test for orthostatic hypotension, take the blood pressure whilst the patient is supine and at rest. Then stand the patient – they must be able to stand for 3 minutes before taking the blood pressure again. If the measurements meet the criteria stated previously, then orthostatic hypotension is evident. If the result is equivocol, record it and request a formal assessment. (Note, the accuracy of orthostatic hypotension has been questioned in recent years.)
Lastly, we conduct statewide outreach to health care organizations. We make and distribute a suite of materials available to encourage accurate and consistent blood pressure self-management in English, Spanish, Russian, Chinese and Vietnamese. We also work closely with Washington Information Network 211 so people can call or search online for places to get their blood pressure checked nearby.
Many mechanisms have been proposed to account for the rise in peripheral resistance in hypertension. Most evidence implicates either disturbances in the kidneys' salt and water handling (particularly abnormalities in the intrarenal renin–angiotensin system)[61] or abnormalities of the sympathetic nervous system.[62] These mechanisms are not mutually exclusive and it is likely that both contribute to some extent in most cases of essential hypertension. It has also been suggested that endothelial dysfunction and vascular inflammation may also contribute to increased peripheral resistance and vascular damage in hypertension.[63][64] Interleukin 17 has garnered interest for its role in increasing the production of several other immune system chemical signals thought to be involved in hypertension such as tumor necrosis factor alpha, interleukin 1, interleukin 6, and interleukin 8.[65]
High blood pressure is the most common chronic medical problem prompting visits to primary health care providers in USA. The American Heart Association estimated the direct and indirect costs of high blood pressure in 2010 as $76.6 billion.[144] In the US 80% of people with hypertension are aware of their condition, 71% take some antihypertensive medication, but only 48% of people aware that they have hypertension adequately control it.[144] Adequate management of hypertension can be hampered by inadequacies in the diagnosis, treatment, or control of high blood pressure.[164] Health care providers face many obstacles to achieving blood pressure control, including resistance to taking multiple medications to reach blood pressure goals. People also face the challenges of adhering to medicine schedules and making lifestyle changes. Nonetheless, the achievement of blood pressure goals is possible, and most importantly, lowering blood pressure significantly reduces the risk of death due to heart disease and stroke, the development of other debilitating conditions, and the cost associated with advanced medical care.[165][166]
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