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Definition
What is hypotension (low blood pressure)?
Hypotension, also called low blood pressure, is a sudden drop in blood pressure below 90/60 mmHg. Hypotension makes blood volume decreased because of lack of heart contraction.
A blood pressure reading appears as two numbers. The first and higher of the two is a measure of systolic pressure, or the pressure in the arteries when the heart beats and fills them with blood. The second number measures diastolic pressure, or the pressure in the arteries when the heart rests between beats.
Therefore, you are considered to have low blood pressure if your reading is less than 90/60, meaning:
- 90 mmHg or less systolic blood pressure, or
- 60 mmHg or less diastolic blood pressure.
Hypotension is a symptom of many medical conditions and can cause many effects on a person’s health, especially in the elderly. However, regular exercise, standing up for too long, or even standing up from a sitting or lying down position can decrease your blood pressure. This is called postural hypotension or orthostatic hypotension.
How common is hypotension (low blood pressure)?
Low blood pressure can happen to anyone. It can be managed by reducing your risk factors. Please discuss with your doctor for further information.
Symptoms
What are the symptoms of hypotension (low blood pressure)?
The symptoms of hypotension (low blood pressure) occur when the blood supply to the brain is reduced. Common symptoms include:
- Feeling lightheaded or dizzy;
- Dizziness or lightheadedness;
- Fainting (syncope);
- Lack of concentration;
- Blurred vision;
- Nausea;
- Cold, clammy, pale skin;
- Rapid, shallow breathing;
- Fatigue;
- Depression;
- Thirst.
Chronic low blood pressure with no symptoms is almost never serious, as some healthy people who exercise regularly tend to have lower blood pressure. But a sudden drop in blood pressure can lead to insufficiency of blood supply to vital organs, especially the brain. Decreased blood volume causes malnourishment multi-organs.
Patients with hypotension often suffer some severe symptoms such as syncope, circulation shock and pulse collapse. There may be some symptoms not listed above. If you have any concerns about a symptom, please consult your doctor.
When should I see my doctor?
In most cases, hypotension isn’t a serious problem. Many people have low blood pressure reading but feel just fine. Sometimes you might feel lightheadedness and dizziness, but it should be no problem if the symptoms don’t interfere with your daily life.
Still it is important to see your doctor if you have hypotension as it can point to other more serious health problem. See your doctor or nurse if you have any of the following symptoms:
- Feeling dizzy or like you might pass out when you stand up longer duration (>5 sec);
- Palpitations (rapid, strong, or irregular heartbeat);
- Blurred vision;
- Nausea;
- Warmth;
- Diaphoresis (excessive sweating);
- Lightheadedness.
Causes
What causes hypotension (low blood pressure)?
There are many causes of hypotension. It can happen if:
- There is not enough fluid in your arteries. This can happen if you lose blood or if you are dehydrated, meaning you do not have enough fluids. You can become dehydrated if:
- You do not drink enough fluids
- You have severe diarrhea or vomiting
- You sweat a lot (for example, during exercise)
- Your heart doesn’t pump strongly enough.
- The nerves and hormones in your body that control the blood vessels are not working properly.
- Pregnancy.
- Hormonal problems such as an underactive thyroid (hypothyroidism), diabetes, or low blood sugar (hypoglycemia).
- Heat exhaustion or heat stroke.
- Some over-the-counter medications.
- Some prescription medicines such as for high blood pressure, depression or Parkinson’s disease.
In some patients, hypotension is tied to another problem, such as:
- Diabetes;
- Parkinson disease;
- Heart failures;
- Heart arrhythmias (abnormal heart rhythms);
- Widening, or dilation, of the blood vessels;
- Liver disease.
But people who are otherwise healthy can have the condition, too. Older people are more likely than younger people to have hypotension. Low blood pressure is also common in pregnant women.
Some cases, blood pressure can drop suddenly. In these cases, causes can be:
- Loss of blood from bleeding;
- Low body temperature;
- High body temperature;
- Heart muscle disease causing heart failure;
- Sepsis, a severe blood infection;
- Severe dehydration from vomiting, diarrhea, or fever;
- A reaction to medication or alcohol;
- A severe allergic reaction, called anaphylaxis.
Risk factors
What increases my risk for hypotension (low blood pressure)?
The risk of both low and high blood pressure normally increases with age. Blood flow to the heart muscle and the brain declines with age, often as a result of plaque buildup in blood vessels. An estimated 10% to 20% of people over age 65 have hypotension.
Some medications can increase your risk of hypotension, such as diuretics, nitrates and vasodilation.
Other risk factors include:
- History of potential volume loss (vomiting, diarrhea, fluid restriction, fever);
- Medical history of congestive heart failure, diabetes, malignancy, alcoholism;
- Evidence of neurologic examination of Parkinsonism, peripheral neuropathy, dysautonomia (such as abnormal pupils response).
Diagnosis & treatment
The information provided is not a substitute for any medical advice. ALWAYS consult with your doctor for more information.
How is hypotension (low blood pressure) diagnosed?
There are a few tests that can help your doctor or nurse find out if hypotension is causing your symptoms. The most common test is to take your blood pressure and pulse while you are sitting or lying down and then again after you stand up. Other tests could include:
- Blood tests to see if you have a condition called anemia, which happens if you have too few red blood cells.
- Blood tests to check that your blood has the right chemical balance and that your fluid levels are in the right range.
- Tests to make sure your heart is pumping correctly.
How is hypotension (low blood pressure) treated?
Low blood pressure that either doesn’t cause signs or symptoms or causes only mild symptoms, such as brief episodes of dizziness when standing, rarely requires treatment.
The first thing your doctor or nurse will want to do to treat your hypotension is found out if it is caused by any medicines you take. If so, he or she might switch you to another medicine or lower your dose. If you have symptoms, the most appropriate treatment depends on the underlying cause, and doctors usually try to address the primary health problem
Depending on your age, health status and the type of low blood pressure you have, you can do this in several ways:
- Increase salt in your diet. Keep in mind to check with your doctor beforehand, as excess sodium can lead to heart failure, especially in older adults.
- Drink more water. This will increase blood volume and fight dehydration.
- Wear compression stockings.
- Several medications can be used to treat low blood pressure that occurs when you stand up (orthostatic hypotension).
Lifestyle changes & home remedies
What are some lifestyle changes or home remedies that can help me manage hypotension (low blood pressure)?
The following lifestyles and home remedies might help you cope with Hypotension but only after you pay a visit to your doctor or nurse:
- Stand up slowly and give your body time to adapt. This is especially important when you get out of bed in the morning. Start by sitting up and waiting a moment. Then swing your legs over the side of the bed and wait some more. When you do stand up, make sure you have something to hold onto in case you start to feel dizzy.
- Avoid running, hiking, or doing anything that takes a lot of energy in hot weather. These things can make orthostatic hypotension worse.
- Make sure you drink enough fluids, especially in hot weather.
- Put blocks under the posts at the head of your bed. This will raise your head above your heart slightly.
- Wear “compression” stockings; ones that go to your waist are most helpful, but they are hard to wear.
- Avoid drinking much alcohol.
If you have any questions, please consult with your doctor to better understand the best solution for you.
Read more post:
Sources:
- Sathyapalan T, Aye MM, Atkin SL. Postural hypotension. BMJ 2011. Medical program. Accessed December 4, 2016.
- Kaplan NM. The promises and perils of treating the elderly hypertensive. Am J Med Sci 1993. Accessed December 4, 2016.
- Fagard RH, De Cort P. Orthostatic hypotension is a more robust predictor of cardiovascular events than nighttime reverse dipping in elderly. Hypertension 2010. Accessed December 4, 2016.
- Braunwald’s The Heart disease, textbook 15th edition. Accessed Oct 10 2016, Download version Page 1032-1035. Accessed December 4, 2016.
- Understanding Low Blood Pressure — the Basics. http://www.webmd.com/heart/understanding-low-blood-pressure-basics. Accessed December 4, 2016.
- Hypotension Symptoms. www.mayoclinic.org/diseases-conditions/low-blood-pressure/basics/definition/con-20032298. Accessed December 4, 2016.
Review Date: April 17, 2017 | Last Modified: April 17, 2017
