Blood pressure is the pressure of blood in your arteries needed to get the blood circulating in your body.

Throughout the day and night, your blood pressure fluctuates; it either goes up or down. It is normal for your blood pressure to go up when you are moving about. The problem starts when your overall blood pressure stays consistently high, even when you are at rest.

High blood pressure means that your blood pressure is always high and that your heart is consistently working harder to pump blood around your body. Usually, your arteries can stretch to cope with occasional high blood pressure. But when the blood pressure is consistently high, the arteries lose their stretchiness, and they become stiff or narrow.

Once the arteries become narrower, it becomes easier for fatty material (atheroma) to deposit and clog them up. If the arteries carrying blood to the heart are damaged or clogged, it can cause a heart attack. If the arteries carrying blood to the brain is damaged or clogged, it can lead to a stroke.

Blood pressure is measured in units of millimeters of mercury (mmHg) with the help of an instrument called a sphygmomanometer. The readings are always in pairs: the systolic value first, followed by the diastolic value.

• Systolic pressure is the measure of pressure in the arteries when the heart contracts. It is the top number on the blood pressure reading.
• Diastolic is the measure of blood pressure when the heart is resting in between beats. It represents the lower number on the blood pressure reading.

The chart below shows measures for normal and high blood pressure.

The cause of high blood pressure cannot always be explained. But in most cases, people develop high blood pressure because of their lifestyle, diet or medical condition. In some cases, high blood pressure runs in families, and it can worsen with age

Some of the causative factors of getting high blood pressure include:

• Smoking
• Drinking too much alcohol
• Not doing enough exercise Being overweight
• Eating too much salt

In a very small number of people, doctors can identify the cause of high blood pressure. This is referred to as secondary hypertension. For example, if your body is producing abnormal hormones from the adrenal glands, it could cause high blood pressure. But after your hormonal condition is treated, your blood pressure will return to normal

Other causes of secondary hypertension include:

• Diabetes
• Kidney disease
• Some medicines, such as over-the-counter medicines, herbal medicines, and oral contraceptives

Before taking any medicines, it is recommended to ask your doctor or pharmacist about their effect on blood pressure.

High blood pressure puts extra strain on your heart, blood vessels and other organs such as kidneys, brain, and eyes. Consistent high blood pressure increases your risk of potentially life-threatening health conditions such as:

• heart attacks
• heart disease
• heart failure
• strokes
• kidney disease
• aortic aneurysms
• peripheral arterial disease
• vascular dementia

If your blood pressure is high, reducing it (by even a small amount) lowers your risk of these serious health conditions.

Hypertension is generally silent; in most cases, it won't show any symptoms. It may take years for the condition to be serious enough to show obvious symptoms.

Symptoms of severe hypertension can include:

• shortness of breath
• headaches
• flushing
• dizziness
• nosebleeds
• chest pain
• dizziness
• blood in the urine

Unfortunately, these symptoms don't occur in everyone having high blood pressure. But waiting for symptoms to develop could be fatal. The best way to know if you have high blood pressure is to measure your blood pressure regularly.

Lifestyle changes:

• Exercise regularly
• If overweight, lose weight
• Avoid sugar and refined carbohydrates
• Eat more potassium and less sodium
• Stop smoking
• Try meditation or yoga
• Sleep well
• Eat healthy high-protein foods
• Consume less alcohol and caffeine

Medicines

If you're diagnosed with high blood pressure, your doctor may recommend taking one or more medicines to keep it under control. These medicines are in tablet form and are to be taken once a day.

Common blood pressure medicines include:

• ACE inhibitors
• angiotensin-2 receptor blockers (ARBs)
• calcium channel blockers
• diuretics
• beta-blockers 
• alpha-blockers
• other diuretics

Some popular brands of medicines for high blood pressure are available at MedsNow:

• Amlodipine
• Ramipril
• Bendroflumethiazide
• Lisinopril
• Felodipine SR
• Lercanidipine
• Istin
• Cardioplen XL
• Bisoprolol
• Perindopril
• Coversyl Arginine
• Zanidip
• Candersartan
• Sevikar
• Amias
• Enalapril
• Teveten
• Atenolol
• Value Health Blood Pressure Monitor
• Losartan
• Alvita Advanced Blood Pressure Arm Monitor
• Adipine
• Indapamide
• Furosemide
• Doxazosin
• Indapamide MR
• Nebivolol

When is high blood pressure an emergency?

High blood pressure causes gradual damage to your body over the years. At times, the blood pressure can rise so quickly and severely that it causes an emergency situation that needs immediate medical attention, and often hospitalisation. During these emergencies, high blood pressure causes the following:

• Stroke
• Heart attack
• Memory loss, trouble concentrating, irritability, personality changes or progressive loss of consciousness
• Pain in the chest
• Fatal damage to your body's main artery
• Shortness of breath due to the sudden impaired pumping of the heart causing fluid to backup in the lungs
• Complications in pregnancy (preeclampsia or eclampsia)
• Sudden loss of kidney function
• Blindness

What are high blood pressure medications that cause tinnitus?

ACE inhibitors and angiotensin receptor blockers (ARBs) that are used to lower the blood pressure may cause tinnitus (ringing in the ears). The good news is that tinnitus caused by taking these medicines is often temporary. The ringing of the ears goes away in a few days or in a few weeks after you stop taking medicine

Which high blood pressure medication causes erectile dysfunction?

Erectile dysfunction (ED) is an occasional side effect of high blood pressure medication such as thiazide diuretics, beta-blockers, and loop diuretics. These medications decrease the blood flow to the penis, thus making it difficult to get an erection. However, other high blood pressure medications, such as alpha-blockers, angiotensin receptor blockers, and ACE inhibitors, rarely cause ED.

Why is blood pressure high during pregnancy?

There are several possible causes of high blood pressure during pregnancy.

These include:

• first-time pregnancy
• age (over 35)
• carrying more than one child
• not getting enough physical activity
• being overweight or obese
• assistive reproductive technology (such as in vitro fertilisation, or IVF)
• having diabetes or certain autoimmune diseases
• a family history of pregnancy-related hypertension
• drinking alcohol
• smoking

What do high blood pressure headaches feel like?

A hypertension headache usually occurs on both sides of your head. The headache is often pulsating and typically gets worse with any activity. You may also experience vision changes, tingling, numbness or shortness of breath.

Can drinking lots of water lower blood pressure?

Yes. If you have hypertension, you should drink twelve 8-ounce glasses or 96 ounces of water per day to lower your blood pressure.

What is normal blood pressure by age?

The table below shows the estimated normal blood pressure by age.