The first chemical for hypertension, sodium thiocyanate, was used in 1900 but had many side effects and was unpopular.[152] Several other agents were developed after the Second World War, the most popular and reasonably effective of which were tetramethylammonium chloride, hexamethonium, hydralazine, and reserpine (derived from the medicinal plant Rauwolfia serpentina). None of these were well tolerated.[159][160] A major breakthrough was achieved with the discovery of the first well-tolerated orally available agents. The first was chlorothiazide, the first thiazide diuretic and developed from the antibiotic sulfanilamide, which became available in 1958.[152][161] Subsequently, beta blockers, calcium channel blockers, angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers, and renin inhibitors were developed as antihypertensive agents.[158]
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.

Excellent point! I can’t speak for anyone specifically, but I can say that generally, doctors make the worst patients. We don’t always follow the textbook guidelines nor abide by health recommendations. Then, there’s genetics, a pretty powerful force, and one over which we have little control. And, of course, there is just plain bad luck (or fate, finger of God, however you choose to describe it). So, many factors can come into play when a doctor gets diagnosed with what can otherwise be considered a preventable disease.
If you had previously been diagnosed with high blood pressure, the new guidelines don't affect you too much, says Dr. Conlin, as you still need to continue your efforts to lower it through medication, diet, exercise, and weight loss. "However, based on new information in the guidelines, your doctor may propose treating your blood pressure to a lower level," he says.
^ Roerecke, Michael; Tobe, Sheldon W.; Kaczorowski, Janusz; Bacon, Simon L.; Vafaei, Afshin; Hasan, Omer S. M.; Krishnan, Rohin J.; Raifu, Amidu O.; Rehm, Jürgen (27 June 2018). "Sex‐Specific Associations Between Alcohol Consumption and Incidence of Hypertension: A Systematic Review and Meta‐Analysis of Cohort Studies". Journal of the American Heart Association. 7 (13): e008202. doi:10.1161/JAHA.117.008202.
Vasovagal reaction is a common condition in which a healthy person temporarily develops low blood pressure, slow heart rate, and sometimes fainting. A vasovagal reaction typically is brought on by emotions of fear or pain such as having blood drawn, starting an intravenous infusion, or by gastrointestinal upset. Vasovagal reactions are caused by activity of the involuntary (autonomic) nervous system, especially the vagus nerve, which releases hormones that slow the heart and widen the blood vessels. The vagus nerve also controls digestive tract function and senses activity in the digestive system. Thus, some people can have a vasovagal reaction from straining at a bowel movement or vomiting. 

When the systolic pressure drops below 90 mm Hg and the diastolic pressure falls below 60 mm Hg, this is categorized as low blood pressure. Some people may have low pressure all the time and this may be normal for them. If they do not experience any other signs or symptoms, medical treatment may not be necessary for them. Low blood pressure becomes a concern when it is accompanied by noticeable symptoms, such as dizziness, fainting and, in severe cases, shock. When this occurs, people should seek medical attention to determine if an underlying condition may be responsible for their hypotension.
We fund research. The research we fund today will help improve our future health. Our Division of Cardiovascular Sciences and its Vascular Biology and Hypertension Branch oversee much of the research we fund on the regulation of blood pressure, pathways involved in high blood pressure, and the complications from uncontrolled high blood pressure. The Center for Translation Research and Implementation Science supports research to translate these discoveries into clinical practice. Search the NIH RePORTer to learn about research NHLBI is funding on high blood pressure
Other causes of dehydration include exercise, sweating, fever, and heat exhaustion or heat stroke. Individuals with mild dehydration may experience only thirst and dry mouth. Moderate to severe dehydration may cause orthostatic hypotension (manifested by lightheadedness, dizziness, or fainting upon standing). Prolonged and severe dehydration can lead to shock, kidney failure, confusion, acidosis (too much acid in the blood), coma, and even death.
When blood pressure is not sufficient to deliver enough blood to the organs of the body, the organs do not work properly and can be temporarily or permanently damaged. Symptoms of low blood pressure caused by conditions or diseases depend upon the specific cause of the low blood pressure. For example, if insufficient blood flows to the brain, brain cells do not receive enough oxygen and nutrients, and a person can feel lightheaded, dizzy, or even faint.
Hypertension is the most important preventable risk factor for premature death worldwide.[149] It increases the risk of ischemic heart disease,[150] strokes,[23] peripheral vascular disease,[151] and other cardiovascular diseases, including heart failure, aortic aneurysms, diffuse atherosclerosis, chronic kidney disease, atrial fibrillation, and pulmonary embolism.[11][23] Hypertension is also a risk factor for cognitive impairment and dementia.[23] Other complications include hypertensive retinopathy and hypertensive nephropathy.[27]
Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.

As you get older, high blood pressure, especially isolated systolic hypertension, is more common and can increase your risk of serious health problems. Treatment, especially if you have other medical conditions, requires ongoing evaluation and discussions with your doctor to strike the best balance of reducing risks and maintaining a good quality of life.
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]
There is no treatment available for the causes of portal hypertension. However, treatment can prevent or manage the complications. Diet, medication (nonselective beta-blockers), endoscopic therapy, surgery, and radiology procedures can all help in treating or preventing symptoms of portal hypertension. If these treatments are unsuccessful in treating symptoms, transjugular intrahepatic portosystemic shunt (TIPS) or distal splenorenal shunt (DSRA) are two procedures that may reduce pressure in the portal veins. Maintaining a healthy lifestyle may help to prevent portal hypertension.
Much of the disease burden of high blood pressure is experienced by people who are not labeled as hypertensive.[87] Consequently, population strategies are required to reduce the consequences of high blood pressure and reduce the need for antihypertensive medications. Lifestyle changes are recommended to lower blood pressure, before starting medications. The 2004 British Hypertension Society guidelines[87] proposed lifestyle changes consistent with those outlined by the US National High BP Education Program in 2002[95] for the primary prevention of hypertension:
According to guidelines from the American Heart Association (AHA) and the American College of Cardiology (ACC), a reading below 120/80 mm Hg is classified as normal blood pressure. Those with a blood pressure reading anywhere from 120/80 up to 129/80 are classified within a category called elevated blood pressure. Hypertension is defined as a reading of 130/80 or higher.
Echocardiogram is an ultrasound examination of the heart It is used to evaluate the anatomy and the function of the heart. A cardiologist is required to interpret this test and can evaluate the heart muscle and determine how thick it is, whether it moves appropriately, and how efficiently it can push blood out to the rest of the body. The echocardiogram can also assess heart valves, looking for narrowing (stenosis) and leaking (insufficiency or regurgitation). A chest X-ray may be used as a screening test to look for heart size, the shape of the aorta, and to assess the lungs.
Everyone age 3 or older should have their blood pressure checked by a healthcare provider at least once a year. Your doctor will use a blood pressure test to see if you have consistently high blood pressure readings. Even small increases in systolic blood pressure can weaken and damage your blood vessels. Your doctor will recommend heart-healthy lifestyle changes to help control your blood pressure and prevent you from developing high blood pressure.

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]

Orthostatic hypotension is caused by a sudden change in body position. This occurs most often when you shift from lying down to standing. This type of low blood pressure usually lasts only a few seconds or minutes. If this type of low blood pressure occurs after eating, it is called postprandial orthostatic hypotension. This type most often affects older adults, those with high blood pressure, and people with Parkinson disease.
Blood pressure is expressed by two measurements, the systolic and diastolic pressures, which are the maximum and minimum pressures, respectively.[1] For most adults, normal blood pressure at rest is within the range of 100–130 millimeters mercury (mmHg) systolic and 60–80 mmHg diastolic.[7][12] For most adults, high blood pressure is present if the resting blood pressure is persistently at or above 130/80 or 140/90 mmHg.[5][7] Different numbers apply to children.[13] Ambulatory blood pressure monitoring over a 24-hour period appears more accurate than office-based blood pressure measurement.[5][10]

In short, everyone. The motivation behind the change was to make people healthier. With more sensitive guidelines, we are able to get in control of our blood pressure sooner and improve heart health before reaching levels that could cause more serious health problems. For some, the changing guidelines may result in antihypertensive (blood pressure lowering) medication, along with lifestyle management, but that will not be the case for everyone.

Heart attack. Signs of heart attack include mild or severe chest pain or discomfort in the center of the chest or upper abdomen that lasts for more than a few minutes or goes away and comes back. It can feel like pressure, squeezing, fullness, heartburn, or indigestion. There may also be pain down the left arm. Women may also have chest pain and pain down the left arm, but they are more likely to have less typical symptoms, such as shortness of breath, nausea, vomiting, unusual tiredness, and pain in the back, shoulders, or jaw. Read more about the signs and symptoms of a heart attack.

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.