- Low Blood Pressure (Hypotension)
- Topic Overview
- When to Worry About Low Blood Pressure
- How low is too low for blood pressure?
- Symptoms of low blood pressure
- Underlying causes of low blood pressure
- If you notice a sudden decline in blood pressure
- Pericarditis Symptoms
- Acute Pericarditis Symptoms
- Chronic Pericarditis Symptoms
- Pericarditis Diagnosis
- Eating can cause low blood pressure
- Dizzy after eating? Feeling lightheaded from a meal could be postprandial hypotension
Low Blood Pressure (Hypotension)
What is low blood pressure?
Low blood pressure means that your blood pressure is lower than normal. Another name for low blood pressure is hypotension (say “hy-poh-TEN-shun”).
In most healthy adults, low blood pressure does not cause problems or symptoms. In fact, it may be normal for you. For example, people who exercise regularly often have lower blood pressure than people who are not as fit.
But if your blood pressure drops suddenly or causes symptoms like dizziness or fainting, it is too low. It can cause shock. Shock can be dangerous if it is not treated right away.
Blood pressure is a measure of how hard the blood pushes against the walls of your arteries as it moves through your body. Blood pressure consists of two numbers: systolic and diastolic.
- The systolic (higher) number shows how hard the blood pushes when the heart is pumping.
- The diastolic (lower) number shows how hard the blood pushes between heartbeats, when the heart is relaxed and filling with blood.
Someone with a systolic pressure of 120 and a diastolic pressure of 80 has a blood pressure of 120/80, or “120 over 80.” Normal blood pressure is lower than 120/80.
Low blood pressure does not have a specific number where it is too low. Most doctors consider blood pressure to be too low when it causes symptoms or drops suddenly. In general, low blood pressure symptoms happen when blood pressure is less than 90/60.
What causes low blood pressure?
Some of the causes of low blood pressure include:
- Getting up after you sit or lie down. This can cause a quick drop in blood pressure called orthostatic hypotension.
- Standing for a long time.
- Not drinking enough fluids (dehydration).
- Medicines, such as high blood pressure medicine or other heart medicines.
- Health problems such as thyroid disease, severe infection, bleeding in the intestines, or heart problems.
- Trauma, such as major bleeding or severe burns.
What are the symptoms?
Many people with low blood pressure don’t have any symptoms.
Symptoms to watch for include:
- Feeling dizzy, lightheaded, or faint.
- Feeling sick to your stomach or vomiting.
- Feeling more thirsty than usual.
- Having blurry vision.
- Feeling weak.
- Being confused.
- Being tired.
- Having cold, clammy skin.
- Breathing very fast.
If you have symptoms of low blood pressure, especially dizziness or fainting, call your doctor.
Watch for symptoms of low blood pressure. Tell your doctor when the symptoms happen so he or she can treat them.
How is low blood pressure diagnosed?
Often people learn that they have low blood pressure when their doctor checks it. Or you may find that you have low blood pressure when you check it at home.
To check for the causes of your low blood pressure, your doctor will ask about your past health, your symptoms, and the medicines you take. He or she will do a physical exam and may do other tests. Your doctor may check for another health problem that could be causing your low blood pressure.
Will your doctor treat low blood pressure?
You will likely get treated for low blood pressure only if it is causing symptoms or if your blood pressure drops suddenly. Treatment depends on your symptoms, how severe they are, and the reasons for the low blood pressure.
Your doctor may have you:
- Add more salt to your diet.
- Get fluid through an intravenous (IV) line if you are very dehydrated.
- Change or stop medicines that lower your blood pressure.
- Take medicine to treat the problem that is causing low blood pressure. For example, you may need antibiotics to treat infection or medicines to stop vomiting or diarrhea.
Be sure to talk with your doctor before you add more salt to your diet or make any changes in your medicines.
How can you prevent low blood pressure symptoms?
If you have orthostatic hypotension, your doctor may suggest that you try some simple ways to prevent symptoms like dizziness. For example, you can:
- Stand up slowly.
- Drink more water.
- Drink little or no alcohol.
- Limit or avoid caffeine.
- Wear compression stockings.
If you feel dizzy or lightheaded, sit down or lie down for a few minutes. Or you can sit down and put your head between your knees. This will help your blood pressure go back to normal and help your symptoms go away.
When to Worry About Low Blood Pressure
- Heart and Vascular Health
- Heart Health
- Thyroid Health
Heart Health News Fall 2018 Jan 8, 2017
We all know that high blood pressure can be dangerous. But what about low blood pressure?
Also called hypotension, low blood pressure is not a problem if you’re healthy and show no signs or symptoms of the condition. However, abnormally low blood pressure can cause problems such as dizziness and fainting and can be a sign that other serious conditions, such as heart disease, are present.
What is Blood Pressure?
Blood pressure is the force of blood pushing on the artery walls as it is pumped out of the heart. Blood pressure is measured in two kinds of pressures. Systolic pressure is when the heart beats while pumping blood. Diastolic pressure is when the heart is at rest between beats.
Blood pressure is measured in millimeters of mercury (mmHg). Systolic pressure is listed first (or the “top” number), then diastolic pressure (or the “bottom” number).
Normal blood pressure in adults is less than 120/80 mmHg. Low blood pressure is a reading below 90/60 mmHg.
Most forms of hypotension happen because your body can’t bring blood pressure back to normal or can’t do it fast enough, says the National Heart, Lung and Blood Institute.
For some people, low blood pressure is normal. They have it all the time, with no symptoms or negative side effects.
In other people, abnormally low blood pressure is caused by certain medical conditions or factors. When this happens, less blood and oxygen flow to the body’s organs.
Symptoms & Causes of Low Blood Pressure
Many different conditions and situations can cause low blood pressure, from standing up too fast to being pregnant. Sometimes, low blood pressure is linked to an underlying problem, says the American Heart Association. That’s why it’s important to see your doctor right away if you experience the signs of low blood pressure.
Symptoms of low blood pressure can include:
- Lack of concentration
- Blurred vision
- Cold, clammy and pale skin
- Rapid, shallow breathing
Low blood pressure can be a sign of serious heart, endocrine or neurological conditions. If left untreated, the brain and other vital organs do not get the oxygen and nutrients they need. In extreme cases, this can cause shock, a life-threatening condition.
If you show signs of low blood pressure, your doctor will conduct an exam and may perform tests to determine what’s causing the condition. Low blood pressure can occur with many other conditions, says the American Heart Association.
Some causes of low blood pressure are:
- Prolonged bed rest, in which circulation decreases due to lack of movement
- Heart problems that prevent the heart from being able to circulate enough blood
- Endocrine problems, such as an under-active thyroid
- Pregnancy. Blood pressure often drops in the first 24 weeks of pregnancy.
- Decrease in blood volume from trauma, dehydration or internal blooding
- Certain medicines. Medicines that treat hypertension, heart conditions, Parkinson’s disease, depression and erectile dysfunction can lower blood pressure.
- Nutritional deficiencies, such as a lack of vitamin B-12 and folic acid, may lead to anemia, which can cause low blood pressure.
- Severe infections like septic shock, when bacteria enter the blood stream
- Severe allergic reaction (anaphylaxis) that causes problems with breathing and sudden drop in blood pressure
- Postural (orthostatic) hypotension, a rapid blood pressure drop when standing from a sitting or lying down position
- Neurally mediated hypotension, which is a blood pressure drop after standing for long periods.
Living with Low Blood Pressure
Medicines and lifestyle changes can help you live safely with chronic low blood pressure. Your doctor can recommend steps you can take to manage your low blood pressure. These actions can help control the condition:
Drink more water. This can help avoid dehydration.
Medicines and lifestyle changes can help you live safely with chronic low blood pressure.
Avoid alcohol. Alcoholic beverages are dehydrating, and alcohol changes how medicines work in your body.
Slow down. Take your time when standing up. If lying down, sit up first. Then wiggle your feet and move your legs. This will increase circulation and get your heart rate up so that you don’t feel lightheaded when you stand up.
If your medicine and lifestyle changes do not reduce your low blood pressure symptoms, talk with your doctor about other changes you can make.
Source: National Heart, Lung and Blood Institute; American Heart Association
How low is too low for blood pressure?
Within certain limits, the lower your blood pressure reading is, the better. There is also no specific number at which day-to-day blood pressure is considered too low, as long as none of the symptoms of trouble are present.
Symptoms of low blood pressure
Most doctors will only consider chronically low blood pressure as dangerous if it causes noticeable signs and symptoms, such as:
- Dizziness or lightheadedness
- Fainting (syncope)
- Dehydration and unusual thirst
- Dehydration can sometimes cause blood pressure to drop. However, dehydration does not always cause low blood pressure. Fever, vomiting, severe diarrhea, overuse of diuretics and strenuous exercise can all lead to dehydration, a potentially serious condition in which your body loses more water than you take in. Even mild dehydration (a loss of as little as 1 percent to 2 percent of body weight) can cause weakness, dizziness and fatigue.
- Lack of concentration
- Blurred vision
- Cold, clammy, pale skin
- Rapid, shallow breathing
Underlying causes of low blood pressure
Low blood pressure can occur with:
- Prolonged bed rest
- Pregnancy: During the first 24 weeks of pregnancy, it’s common for blood pressure to drop.
- Decreases in blood volume: A decrease in blood volume can also cause blood pressure to drop. A significant loss of blood from major trauma, dehydration or severe internal bleeding reduces blood volume, leading to a severe drop in blood pressure.
- Certain medications: A number of drugs can cause low blood pressure, including diuretics and other drugs that treat hypertension; heart medications such as beta blockers; drugs for Parkinson’s disease; tricyclic antidepressants; erectile dysfunction drugs, particularly in combination with nitroglycerine; narcotics and alcohol. Other prescription and over-the-counter drugs may cause low blood pressure when taken in combination with high blood pressure medications.
- Heart problems: Among the heart conditions that can lead to low blood pressure are an abnormally low heart rate (bradycardia), problems with heart valves, heart attack and heart failure. Your heart may not be able to circulate enough blood to meet your body’s needs.
- Endocrine problems: Such problems include complications with hormone-producing glands in the body’s endocrine systems; specifically, an underactive thyroid (hypothyroidism), parathyroid disease, adrenal insufficiency (Addison’s disease), low blood sugar and, in some cases, diabetes.
- Severe infection (septic shock): Septic shock can occur when bacteria leave the original site of an infection (most often in the lungs, abdomen or urinary tract) and enter the bloodstream. The bacteria then produce toxins that affect blood vessels, leading to a profound and life-threatening decline in blood pressure.
- Allergic reaction (anaphylaxis): Anaphylactic shock is a sometimes-fatal allergic reaction that can occur in people who are highly sensitive to drugs such as penicillin, to certain foods such as peanuts or to bee or wasp stings. This type of shock is characterized by breathing problems, hives, itching, a swollen throat and a sudden, dramatic fall in blood pressure.
- Neurally mediated hypotension: Unlike orthostatic hypotension, this disorder causes blood pressure to drop after standing for long periods, leading to symptoms such as dizziness, nausea and fainting. This condition primarily affects young people and occurs because of a miscommunication between the heart and the brain.
- Nutritional deficiencies: A lack of the essential vitamins B-12 and folic acid can cause anemia, which in turn can lead to low blood pressure.
If you notice a sudden decline in blood pressure
A single lower-than-normal reading is not cause for alarm, unless you are experiencing any other symptoms or problems. If you experience any dizziness, lightheadedness, nausea or other symptoms, it’s a good idea to consult with your healthcare provider. To help with your diagnosis, keep a record of your symptoms and activities at the time they occurred.
Is low blood pressure related to low heart rate? Find out.
Signs of pericarditis may come on suddenly, or develop slowly over time.
Within the chest cavity, the heart is protected and held in place by a membranous sac called the pericardium.
Various issues, including infections, heart attacks, trauma, and autoimmune disorders, can cause the pericardium to become inflamed and swollen — a condition called pericarditis.
Depending on the cause, pericarditis can either be acute (short-term) or chronic (long-term).
The acute and chronic forms of pericarditis have different symptoms.
Acute Pericarditis Symptoms
Chest pain is the most common symptom of acute pericarditis.
This pain is typically described as sharp and stabbing, likely a result of the heart rubbing against the inflamed pericardium (this symptom is sometimes called pericardial rub).
Additionally, the chest pain from pericarditis may:
- Come on quickly
- Primarily be felt in the middle or left side of the chest, but may also affect the neck, shoulders, back, or abdomen
- Worsen while lying down and breathing deep, and ease up when sitting up and leaning forward
- Resemble chest pain from a heart attack
Aside from chest pain, other symptoms of acute pericarditis include fever, weakness, trouble breathing, coughing, and heart palpitations, or a noticeably irregular heartbeat.
Chronic Pericarditis Symptoms
One type of chronic pericarditis is called chronic effusive pericarditis, which develops when excess fluid gathers in the space between the heart and pericardium.
Like acute pericarditis, the most common symptom of chronic effusive pericarditis is chest pain.
Other common symptoms include tiredness, coughing, and shortness of breath.
Severe cases of chronic effusive pericarditis may cause hypotension, or low blood pressure, and swelling in the stomach (ascites) and extremities (edema).
A type of chronic pericarditis called chronic constrictive pericarditis may develop as a complication of acute pericarditis.
A rare disease, chronic constrictive pericarditis is marked by stiff, scar-like pericardium tissue that restricts the movement of the heart.
It can be life threatening, causing the following symptoms:
- Difficulty breathing
- Weakness and fatigue
- Ascites and edema
- Abdominal pain, nausea, and vomiting
Diagnosis of pericarditis begins with your doctor getting your medical history.
You’ll be asked about your symptoms, as well as any recent respiratory infections, heart attacks, injuries, and other medical conditions you may have had.
The next diagnostic step is a physical exam, during which your doctor will look for signs of excess fluid in your chest and pericardial rubbing — this is typically done with a stethoscope while you are leaning forward and breathing in and out.
In severe cases, your doctor may also hear crackles in your lungs, pericardial effusion (fluid between your pericardium and heart), and signs of fluid in the space around your lungs.
Your doctor may then order one or more imaging and diagnostic tests, including:
- Electrocardiogram, or EKG, which analyses your heart’s electrical activity
- Chest X-rays, which can show if you have an enlarged heart or excess pericardial fluid
- Cardiac computer tomography (CT) scans, which provide more information than chest X-rays and can help rule out other causes of your symptoms
- Cardiac magnetic resonance imaging (MRI), which can show changes in the pericardium
- Echocardiography, which uses sound waves to image the heart, examine how well its working, and detect excess fluid in the pericardial sac
- Blood tests, which can detect if you have had or are having a heart attack, evaluate your heart’s function and how inflamed your pericardium is, and help determine the cause of your pericarditis
Eating can cause low blood pressure
Dizzy after eating? Feeling lightheaded from a meal could be postprandial hypotension
Updated: August 22, 2018Published: July, 2010
What is postprandial hypotension? Do you sometimes feel dizzy or lightheaded after eating a meal? If so, you could have a common condition called postprandial hypotension (the term loosely translates to low blood pressure after eating) that affects up to one-third of older men and women.
Digestion is a complicated job that requires precise coordination between the digestive, nervous, and circulatory systems. An early task is rerouting extra blood to the stomach and small intestine. To compensate for this diversion, the heart beats faster and harder while blood vessels far from the digestive system narrow. These two actions maintain blood pressure and blood flow to the brain, legs, and everywhere in between.
In some people, the heart and blood vessels don’t respond as they should. That causes blood pressure to decrease everywhere but the digestive system. The sudden drop usually announces itself as dizziness or lightheadedness. Postprandial hypotension causes some people to fall, others to faint. It can trigger the chest pain known as angina, disturb vision, or cause nausea. It has even been reported to trigger the mini-strokes known as transient ischemic attacks.
Postprandial hypotension and blood pressure
Some people are genetically predisposed to postprandial hypotension. In others, it comes on after a stroke, accident, or other trauma damages key nerves or blood pressure sensors. In most people, though, postprandial hypotension stems from aging-related changes that interfere with the body’s ability to respond quickly to sudden changes in blood pressure.
A major culprit is high blood pressure, which stiffens arteries, making it harder for them to narrow and relax as needed. Failure of blood pressure sensors in the arteries or stretch receptors in the stomach (which alert other parts of the body that eating is under way) can lead to postprandial hypotension, as can diabetes, Parkinson’s disease, and other nerve-damaging conditions.
How to prevent feeling dizzy after eating
There is no surefire treatment for postprandial hypotension, but these 4 lifestyle changes can help you prevent low blood pressure:
- Water before meals. Drinking 12 to 18 ounces of water 15 minutes before eating can blunt a fall in blood pressure.
- Smaller meals. Larger meals are more likely to trigger postprandial hypotension than smaller ones. Try switching from three square meals a day to six or seven smaller meals.
- Fewer rapidly digested carbs. White bread and other foods made with highly refined flour, white rice, potatoes, and sugary beverages pass quickly from the stomach to the small intestine. This rapid transit contributes to postprandial hypotension. Cutting back on these foods in favor of slowly digested whole grains, beans, protein, and healthy oils may keep your blood pressure up after a meal.
- Easy does it. Blood pressure usually hits bottom 30 to 60 minutes after a meal. Sitting or lying down for an hour or so after eating is another way to cope with postprandial hypotension. If you need to move around, be careful and be alert for signs that your blood pressure is low.
Various medications and supplements have been tested against postprandial hypotension. These include caffeine, guar gum (a water-soluble fiber), acarbose (a diabetes drug that slows the digestion of carbohydrates), midodrine (a blood pressure booster), and others. But none of them has performed well in clinical trials, and side effects of these therapies can sometimes be worse than postprandial hypotension.
If you often feel odd after eating, tell your doctor. He or she can work with you to see if the feelings are due to postprandial hypotension or something else, and help you find ways to ease the problem.
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