Why Is My Bottom Blood Pressure Number High?

Medically Reviewed on 12/2/2022
high diastolic blood pressure
Isolated diastolic hypertension (IDH) occurs when only your diastolic blood pressure is high

Blood pressure is the force of your blood pushing against the walls of your arteries, which carry blood to other parts of your body. Your blood pressure can be measured using two numbers: 

  • Systolic (the number on top): pressure exerted when the heart pumps blood throughout the body
  • Diastolic (the number at the bottom): pressure exerted when the heart relaxes and refills with blood

When your blood pressure is consistently higher than 130/80 mm Hg, you are considered to have hypertension.

What are the different blood pressure levels?

The table shows different blood pressure levels and conditions.

Table: Blood pressure levels
Blood pressure levels Systolic (mm Hg) Diastolic (mm Hg)
Normal blood pressure Less than 120 Less than 80
Elevated blood pressure or prehypertension Between 120 to 129 Less than 80
Stage 1 hypertension Between 130 to 139 Between 80 to 89
Stage 2 hypertension 140 or higher 90 or higher
Hypertensive crisis Higher than 180 Higher than 120

What is isolated diastolic hypertension?

With hypertension, typically both systolic and diastolic blood pressures are elevated. However, isolated diastolic hypertension (IDH) occurs when your systolic blood pressure is normal, and only your diastolic blood pressure is high (over 80 mm Hg).

IDH is an uncommon type of hypertension, accounting for less than 20% of all hypertension cases. Like other types of hypertension, IDH can increase the risk of stroke, heart disease, heart attack, heart failure, aneurysm, atrial fibrillation, peripheral arterial disease, vision loss, and chronic kidney disease.

What causes the diastolic to be high?

Possible causes of isolated diastolic hypertension include:

What causes your blood pressure to suddenly get high?

Hypertension or high blood pressure (high BP) is a medical condition
Hypertension or high blood pressure (high BP) is a medical condition

Hypertension or high blood pressure (high BP) is a medical condition where the pressure in the arteries is persistently elevated. The heart pumps blood into the arteries, and it is circulated to all parts of the body. Hypertension develops when the heart constantly needs to exert higher force to deliver blood to the organs through the arteries. Since a hypertensive heart must work harder to deliver blood, hypertension can increase the risk of cardiovascular disease, heart attack, and heart failure. Also, the blood vessels in people with hypertension are narrower, putting them at risk of stroke, kidney disease, and vision loss.

There are many reasons for high blood pressure. Some possible causes include

  • caffeine,
  • acute stress or anxiety,
  • certain medications (such as nonsteroidal anti-inflammatory drugs),
  • combinations of medications,
  • recreational drugs,
  • sudden or acute pain,
  • dehydration and
  • white coat effect (fear of being in a hospital or doctor’s clinic).


How to Lower Blood Pressure: Exercise and Tips See Slideshow

What are symptoms of high diastolic pressure?

Hypertension is generally considered a silent killer. Most people with hypertension do not have any symptoms.

It may take many years for the condition to become severe and for symptoms to appear. Many times, these symptoms may be attributed to other issues. The best way to know the blood pressure levels is through regular checkups.

Symptoms of severe hypertension include:

What are the main types of hypertension?

There are two types of hypertension:

1. Primary or essential hypertension

Primary or essential hypertension is when hypertension has no identifiable cause (for example, another disease or condition). It develops gradually over years.

This type of hypertension may be the result of multiple factors, including:

  • Blood plasma volume
  • Hormone activity
  • Genes
  • Physical changes in the body due to age
  • Environmental factors, such as stress and lack of exercise

2. Secondary hypertension

In some people, hypertension is caused by an underlying health condition. This type of hypertension tends to appear suddenly. Secondary hypertension also generally causes higher blood pressure than primary hypertension.

Secondary hypertension is caused by specific conditions and their complications:

  • Kidney disease
  • Congenital heart defects
  • Congenital defects in blood vessels
  • Obstructive sleep apnea
  • Certain endocrine tumors
  • Adrenal gland tumors
  • Cushing syndrome
  • Congenital adrenal hyperplasia
  • Thyroid problems
  • Pregnancy
  • Obesity
  • Certain medications, such as birth control pills, cold remedies, decongestants, pain relievers, and some prescription drugs
  • Use of illegal drugs, such as cocaine and amphetamines

How is high diastolic blood pressure treated?

Isolated diastolic blood pressure can often be managed with lifestyle modifications, dietary supplements, and medications.

Lifestyle modifications

  • Maintaining a healthy weight
  • Eating a high-fiber diet rich in fruits and vegetables and low in saturated fat and dairy products
  • Reducing sodium in the diet
  • Exercising regularly
  • Quitting smoking
  • Limiting alcohol use
  • Managing stress
  • Getting adequate sleep
  • Practicing slow deep breathing
  • Monitoring blood pressure at home

Dietary supplements

Dietary supplements that may help lower blood pressure include:


If lifestyle and dietary changes are not enough to lower your blood pressure, your doctor may be able to prescribe medications for you.

What are the risk factors of high blood pressure?

Factors that increase the risk of hypertension include:

Medically Reviewed on 12/2/2022
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