In the 19th and 20th centuries, before effective pharmacological treatment for hypertension became possible, three treatment modalities were used, all with numerous side-effects: strict sodium restriction (for example the rice diet[152]), sympathectomy (surgical ablation of parts of the sympathetic nervous system), and pyrogen therapy (injection of substances that caused a fever, indirectly reducing blood pressure).[152][158]

Being overweight increases the risk of getting hypertension and increases the workload required of your heart. Diets designed to control blood pressure are often designed to reduce calories as well. Most of these diets require decreasing consumption of fatty foods and sugars while increasing your intake of lean protein, fiber, fruits, and vegetables. A weight loss of just 10 pounds can make a significant difference in your blood pressure.
The new guidelines stem from the 2017 results of the Systolic Blood Pressure Intervention Trial (SPRINT), which studied more than 9,000 adults ages 50 and older who had systolic blood pressure (the top number in a reading) of 130 mm Hg or higher and at least one risk factor for cardiovascular disease. The study's aim was to find out whether treating blood pressure to lower the systolic number to 120 mm Hg or less was superior to the standard target of 140 mm Hg or less. The results found that targeting a systolic pressure of no more than 120 mm Hg reduced the chance of heart attacks, heart failure, or stroke over a three-year period.
Calcium channel blockers are drugs that reduce the movement of calcium into cells of the heart and vessels. This reduces the strength of heart contractions and relaxes the arteries, allowing them to remain more open, lowering blood pressure. Side effects of calcium channel blockers can include heart palpitations, dizziness, swollen ankles, and constipation. Calcium channel blockers can be taken alone or with other blood pressure medications. They should be taken with food or milk. Because of potential interactions, those taking calcium channel blockers should avoid alcohol and grapefruit juice.

Exercise stress test: More commonly used for patients with borderline hypertension. This usually involves pedaling a stationary bicycle or walking on a treadmill. The stress test assesses how the body's cardiovascular system responds to increased physical activity. If the patient has hypertension this data is important to know before the exercise test starts. The test monitors the electrical activity of the heart, as well as the patient's blood pressure during exercise. An exercise stress test sometimes reveals problems that are not apparent when the body is resting. Imaging scans of the heart's blood supply might be done at the same time.

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.)
^ Jump up to: a b c d e f James, PA.; Oparil, S.; Carter, BL.; Cushman, WC.; Dennison-Himmelfarb, C.; Handler, J.; Lackland, DT.; Lefevre, ML.; et al. (Dec 2013). "2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults: Report From the Panel Members Appointed to the Eighth Joint National Committee (JNC 8)". JAMA. 311 (5): 507–20. doi:10.1001/jama.2013.284427. PMID 24352797.
Researchers at the University of Melbourne and Macquarie University have uncovered unusual activity between neurons controlling breathing and blood pressure during the development of essential hypertension. Essential hypertension, which is high blood pressure with no known cause, affects 30% of the global population and is a major contributor to cardiovascular disease.
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).                                                                                                                                                                                                

Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated.[10] High blood pressure typically does not cause symptoms.[1] Long-term high blood pressure, however, is a major risk factor for coronary artery disease, stroke, heart failure, atrial fibrillation, peripheral vascular disease, vision loss, chronic kidney disease, and dementia.[2][3][4][11]
In Europe hypertension occurs in about 30-45% of people as of 2013.[12] In 1995 it was estimated that 43 million people (24% of the population) in the United States had hypertension or were taking antihypertensive medication.[141] By 2004 this had increased to 29%[142][143] and further to 32% (76 million US adults) by 2017.[7] In 2017, with the change in definitions for hypertension, 46% of people in the United States are affected.[7] African-American adults in the United States have among the highest rates of hypertension in the world at 44%.[144] It is also more common in Filipino Americans and less common in US whites and Mexican Americans.[6][145] Differences in hypertension rates are multifactorial and under study.[146]
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.
As of 2014, approximately one billion adults or ~22% of the population of the world have hypertension.[137] It is slightly more frequent in men,[137] in those of low socioeconomic status,[6] and it becomes more common with age.[6] It is common in high, medium, and low income countries.[137][138] In 2004 rates of high blood pressure were highest in Africa, (30% for both sexes) and lowest in the Americas (18% for both sexes). Rates also vary markedly within regions with rates as low as 3.4% (men) and 6.8% (women) in rural India and as high as 68.9% (men) and 72.5% (women) in Poland.[139] Rates in Africa were about 45% in 2016.[140]
You can have high blood pressure, or hypertension, and still feel just fine. That's because high blood pressure often does not cause signs of illness that you can see or feel. But, high blood pressure, sometimes called "the silent killer," is very common in older people and a major health problem. If high blood pressure isn't controlled with lifestyle changes and medicine, it can lead to stroke, heart disease, eye problems, kidney failure, and other health problems. High blood pressure can also cause shortness of breath during light physical activity or exercise.
Secondary hypertension results from an identifiable cause. Kidney disease is the most common secondary cause of hypertension.[23] Hypertension can also be caused by endocrine conditions, such as Cushing's syndrome, hyperthyroidism, hypothyroidism, acromegaly, Conn's syndrome or hyperaldosteronism, renal artery stenosis (from atherosclerosis or fibromuscular dysplasia), hyperparathyroidism, and pheochromocytoma.[23][47] Other causes of secondary hypertension include obesity, sleep apnea, pregnancy, coarctation of the aorta, excessive eating of liquorice, excessive drinking of alcohol, and certain prescription medicines, herbal remedies, and illegal drugs such as cocaine and methamphetamine.[23][48] Arsenic exposure through drinking water has been shown to correlate with elevated blood pressure.[49][50]
For a normal reading, your blood pressure needs to show a top number (systolic pressure) that’s between 90 and less than 120 and a bottom number (diastolic pressure) that’s between 60 and less than 80. The American Heart Association (AHA) considers blood pressure to be within the normal range when both your systolic and diastolic numbers are in these ranges.
People with stage 1 hypertension who don't meet these criteria should be treated with lifestyle modifications. These include: starting the "DASH" diet, which is high in fruit, vegetables and fiber and low in saturated fat and sodium (less than 1,500 mg per day); exercising for at least 30 minutes a day, three times a week; and restricting alcohol intake to less than two drinks a day for men and one drink a day for women, said vice chairman of the new guidelines, Dr. Robert Carey, a professor of medicine and dean emeritus at the University of Virginia Health System School of Medicine. [6 Healthy Habits Dramatically Reduce Heart Disease Risk in Women]
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.
Blood spots in the eyes : Blood spots in the eyes (subconjunctival hemorrhage) are more common in people with diabetes or high blood pressure, but neither condition causes the blood spots. Floaters in the eyes are also not related to high blood pressure. However, an eye doctor (ophthalmologist) may be able to detect damage to the optic nerve caused by untreated high blood pressure.   

Unlike high blood pressure symptoms, which are poorly defined and often totally absent, low blood pressure symptoms tend to be more upfront and easily recognizable. The development of symptoms is often a warning sign of a potentially serious underlying disorder. Generally speaking, your blood pressure would need to fall pretty dramatically before symptoms develop.