WHAT IS IT?
High blood pressure is a condition in which the force of the blood against your artery walls elevates to the point that it can cause health problems.
Blood pressure is determined by the amount of blood your heart pumps and the amount of resistance to blood flow in your arteries. The more blood your heart pumps and the narrower your arteries, the higher your blood pressure.

Types
There are two types of high blood pressure.
  • Primary hypertension
For most adults, there’s no identifiable cause of their high blood pressure. This type, called primary (essential) hypertension, tends to develop gradually over many years.
  • Secondary hypertension
 In some people, high blood pressure results from an underlying condition. This is known as secondary hypertension. Conditions that can lead to secondary hypertension include kidney problems, adrenal gland tumors, thyroid problems, certain blood vessel defects, and obstructive sleep apnea. So can some medications, alcohol abuse, and illegal drugs.

WHAT’S THE CAUSE?
High blood pressure becomes more common with age. It’s also more common in blacks than in whites, and it tends to run in families. Other factors that can increase your risk of high blood pressure include being overweight, not getting enough exercise, using tobacco, consuming too much salt (sodium), drinking too much alcohol, and experiencing high levels of stress.
Most people have no signs or symptoms, even when blood pressure readings reach quite high levels.
Signs and symptoms such as dull headaches, dizzy spells, or a few more nosebleeds than normal often don’t occur until the condition has reached a severe or life-threatening stage.

TREATMENT
High blood pressure is generally diagnosed after taking blood pressure readings at three or more separate appointments. This is because your blood pressure normally varies throughout the day and it can rise during doctor visits.
Primary hypertension is treated with medication. In the case of secondary hypertension, treating the underlying condition may cause your blood pressure to drop.

Types
There are a number of medications to treat high blood pressure. In some cases, a combination of drugs may be used. Thiazide diuretics, Beta-blockers, Angiotensin-converting enzyme (ACE) inhibitors, Calcium channel blockers, Renin inhibitors. 
 
WHAT’S TOO HIGH?
Normal blood pressure
Your blood pressure is normal if it’s below 120/80 millimeters of mercury (mm Hg). Some doctors recommend 115/75 mm Hg as a better goal.

Prehypertension
Prehypertension is a systolic pressure ranging from 120 to 139 mm Hg or a diastolic pressure ranging from 80 to 89 mm Hg. It tends to worsen over time.

Stage 1 hypertension
In stage 1 hypertension, the systolic pressure ranges from 140 to 159 mm Hg or the diastolic pressure from 90 to 99 mm Hg.

Stage 2 hypertension
Stage 2 hypertension is a systolic pressure of 160 mm Hg or higher or a diastolic pressure of 100 mm Hg or higher.

LIFESTYLE
Your doctor may recommend several lifestyle changes, including eating a healthier diet with less salt, exercising regularly, losing weight, quitting smoking, limiting alcohol, and managing stress.

      Excerpt From: The Mayo Clinic. “Mayo Clinic A to Z Health Guide”.