What is low blood pressure?
Low blood pressure (hypotension) occurs when blood pressure drops below the normal range. Doctors generally define low blood pressure as 90/60 mm Hg or below, commonly said as “90 over 60” Usually, doctors only treat hypotension if it is severe enough to cause symptoms.
Low blood pressure can be temporary, or it can be a chronic (long-lasting) condition. The main types of hypotension are:
- Orthostatic hypotension: People with orthostatic hypotension (sometimes called postural hypotension) feel faint or lightheaded when they stand up or change position suddenly.
- Postprandial hypotension: This condition causes people to feel lightheaded or dizzy after eating a meal because their blood pressure drops suddenly.
- Neurally mediated hypotension: People with this disorder feel faint, dizzy, and nauseous after exercising or standing for a long time.
- Severe hypotension linked to shock: Shock is the most extreme form of hypotension. When a person is in shock, blood pressure drops to dangerously low levels, and the brain and organs can’t get enough blood to function.
What is blood pressure?
As blood pumps through the circulatory system, it pushes against the walls of the arteries and veins. Blood pressure is the force of the blood as it presses against the blood vessel walls. It is measured in systolic pressure (when the blood is pumping) and diastolic pressure (between beats, when your heart is at rest).
Blood pressure rises and falls throughout the day. Normal blood pressure is considered to be below 120/80 mm Hg. In a blood pressure reading, the top number refers to systolic pressure, and the bottom number refers to the diastolic pressure.
How common is low blood pressure?
Hypotension is fairly common, and different types are more likely to occur in certain groups of people. Orthostatic hypotension is common in pregnant women and older adults. Postprandial hypotension is common in older people.
Who is affected by low blood pressure?
Low blood pressure can affect people of all ages, although it is more common in older people who are frail or bedridden. Pregnant women and older adults are more likely to have orthostatic hypotension. Children and young adults are most likely to experience neurally mediated hypotension, but they often outgrow it.
Hypotension commonly affects people who:
- Are taking certain medications that cause low blood pressure.
- Have hormonal imbalances or vitamin deficiencies.
- Also have heart problems or liver disease.
What causes low blood pressure?
Low blood pressure is often a sign of another medical condition. Hypotension has a variety of causes. They include:
- Dehydration.
- Heart disease or other heart problems, such as fast heart rate (tachycardia) or very slow heart rate (bradycardia).
- Certain medications, such as those for depression, Parkinson’s disease, or erectile dysfunction.
- Pregnancy.
- Intense emotions like fear or pain.
- Blood loss or blood infection.
- Extreme changes in body temperature.
What are the symptoms of low blood pressure?
Symptoms of low blood pressure can come on suddenly or slowly get worse over time. They include:
- Dizziness, lightheadedness, and fainting.
- Nausea.
- Blurred vision.
- Skin that is cold and sweaty.
- Fatigue.
- Quick, shallow breathing.
What can you do to help relieve symptoms of low blood pressure?
Depending on the type of low blood pressure you have, you may be able to relieve some of your symptoms by:
- Eating a healthy diet with fewer carbohydrates and smaller meals.
- Drinking more water and avoiding alcohol.
- Getting up slowly after you’ve been sitting or lying down.
- Focusing on breathing a few times before you change position.
- Wearing compression stockings.