Blood pressure is the force exerted by the blood flowing in the blood vessels on the walls of the vessels. Without this force, oxygen and nutrients would not reach the tissues and organs of the body. The heart exerts this pressure by forcing the blood out with every contraction. The increase or decrease of blood pressure depends on the circumference of the blood vessel and the force by which the heart pumps the blood
Blood pressure is the force exerted by the blood flowing in the blood vessels on the walls of the vessels. Without this force, oxygen and nutrients would not reach the tissues and organs of the body. The heart exerts this pressure by forcing the blood out with every contraction. The increase or decrease of blood pressure depends on the circumference of the blood vessel and the force by which the heart pumps the blood.
The normal blood pressure is 120/80 mmHg, which is measured using a sphygmomanometer. The reading consists of two figures:
Systolic pressure - It is the higher value, which indicates the contractions of the heart.
Diastolic pressure - It is the lower value and indicates the resting period between heartbeats.
The blood pressure can vary by up to 30 to 40 mmHg during a day. Blood pressure is high during exercise, stress, and anxiety, and the lowest while sleeping.
Hypotension is the medical term used to describe blood pressure less than 90/60 mmHg. Slight fall in the blood pressure causes no problem in healthy individuals. But abnormally low pressure can cause fainting and dizziness, and can also be fatal.
When the pressure falls suddenly, you might have signs and symptoms like:
Lack of concentration.
The different types of hypotension are:
Orthostatic or Postural Hypotension - Orthostatic or postural hypotension is caused due to a sudden drop in the pressure, which results from a change in posture, for example, getting up after sitting or lying. The pressure returns to normal quickly.
Postprandial Hypotension - In older people with diabetes and high blood pressure, the blood pressure drops after eating. For digestion, the intestines need more blood, so the heart beats faster to pump more blood and other blood vessels become narrow to maintain the blood pressure. As a person ages, this process becomes less effective.
Neurally Mediated Hypotension - On standing, the blood gets collected in the legs, and the heart adjusts to maintain normal pressure. But in neurally mediated hypotension, due to problems in signals sent between the heart and the brain, the heart rate and blood pressure drop.
Multiple System Atrophy with Orthostatic Hypotension - Here, low blood pressure results due to continuous damage to the autonomic nervous system, which controls the blood pressure. This condition is also called Shy-Drager syndrome.
Many factors can cause hypotension. Some of the common reasons are:
Heart Problems - In heart conditions like bradycardia (low heart rate), heart attack, heart failure, and heart valve problems, the blood pressure becomes low as the heart cannot pump enough blood.
Medications - Some medicines like alpha blockers, beta blockers, and diuretics are used to lower high blood pressure. Other medicines that can lower the blood pressure are tricyclic antidepressants, Parkinson’s disease drugs, and Sildenafil (Viagra).
Hormonal Imbalance - Any problem in the thyroid or the adrenal gland can cause hormonal imbalance and can lower the blood pressure. The thyroid gland controls the heart rate and blood pressure, and the adrenal gland is responsible for stress response.
Eating Disorders - People with anorexia nervosa and bulimia have abnormally slow heart rate and irregular heartbeats, which can lead to serious hypotension and heart failure.
Pregnancy - As the circulatory system expands during pregnancy, the systolic pressure falls 5 to 10 points, and the diastolic pressure falls 10 to 15 points.
Surgery - Intentionally lowering the blood pressure during surgery results in less blood loss.
Dehydration - When you lose more water and nutrients than you consume, it can cause dizziness and weakness.
Septicemia - Septicemia is when an infection enters the bloodstream. This results in a drastic drop in the blood pressure called septic shock, which can be fatal.
Anaphylaxis - Anaphylaxis is a severe allergic reaction which can be triggered by food, medicines, and insect bites. It causes hives, breathing problems, drop in blood pressure, and swollen throat.
Nutritional Deficiency - Vitamin B12 and folate deficiency can cause anemia, which can lead to hypotension.
Other Causes - Actions like swallowing, coughing, urinating, and emptying your bowel can stimulate the vagus nerve, which raises acetylcholine levels in the body. Acetylcholine reduces blood pressure by dilating the blood vessels.
Severe hypotension can result in shock, which can be life-threatening. The signs and symptoms of shock are:
Cold and clammy skin.
Weak and rapid pulse.
Shallow and rapid breathing.
Seek immediate medical attention if you notice any of these symptoms.
Some types of hypotension depend on the following factors:
Age - Postural hypotension is common in people older than 65 years, and the neurally mediated type is usually seen in children and young adults.
Certain Health Conditions - Conditions like diabetes, Parkinson’s disease, and heart problems increase the risk of low blood pressure.
Medicines - As already mentioned, taking certain drugs can lower blood pressure.
Most doctors consider the blood pressure to be low only if it causes symptoms. Apart from checking your blood pressure, the doctor might order the following tests to know the cause of hypotension.
Blood Test - To check if you have anemia or diabetes or hypoglycemia (low blood sugar).
ECG, Echocardiogram, and Stress Test - These tests are done to detect irregularities in heart rhythm, problems with the blood and oxygen supply to the heart, and structural abnormalities of the heart.
Tilt Table Test - Here, you lie on a table that is tilted and the upper part of your body is raised to simulate orthostatic hypotension.
Hypotension usually gets better by treating the underlying health condition. The goal is to raise blood pressure and reduce the signs and symptoms. The following measures are helpful:
More salt in food as sodium is known to raise blood pressure.
Drink a lot of fluids to prevent dehydration.
Compression stockings reduce the pooling of blood in the legs seen in postural hypotension.
For orthostatic hypotension, medications like Fludrocortisone and Midodrine can help.
The symptoms caused by low blood pressure can be prevented by:
Drinking more water.
Consuming less alcohol.
Take a healthy diet.
Eat small meals and a low-carbohydrate diet.
While getting up from the bed in the morning, take a few deep breaths and stand up after sitting for some time.
You can learn how to prevent and manage the symptoms effectively by identifying the triggers, and by trying to avoid them as much as possible. Keep monitoring your blood pressure at home, and if it remains low the majority of times and if it is causing symptoms, consult a cardiologist online.
The following foods can be given to patients with low blood pressure.
- Low carbohydrate-containing foods.
- Increase the intake of water.
- Foods that are rich in vitamin B12 such as eggs, meat, milk products, fortified breakfast cereals, and nutritional yeast products.
- Foods that are rich in folate content such as dark leafy green vegetables, fruits, nuts, beans, eggs, dairy, meat, poultry, seafood, and grains.
- Caffeine is an excellent option to raise blood pressure immediately.
Low blood pressure is a severe condition in which the patient may faint at any place. Therefore, when a person realizes that his or her blood pressure is falling low, the patient can immediately drink salted lime juice or caffeine. They are excellent blood pressure boosters in emergencies.
Whenever you need to raise your blood pressure suddenly, you can eat any food that is rich in salt content like salted lime juice. You may also intake caffeine that is also capable of raising your blood pressure immediately.
The following are the symptoms that will be experienced by a person with low blood pressure.
- A feeling of dizziness or lightheadedness.
- Blurred or darkly fading vision.
- Lack of concentration.
- A sudden feeling of weak legs.
Citrus fruits are rich in bioflavonoids. These bioflavonoids are known to contain hesperidin. They contain certain antioxidants and that can reduce blood pressure. Supplementation of vitamin C by consuming citrus fruits is known to decrease the risk of high blood pressure.
Yes, emotional stress can lead to low blood pressure. Along with stress, many other factors can also contribute to low blood pressure. It includes fear, insecurity, and pain, which are the most common causes of fainting.
You can follow the home remedies mentioned below to treat low blood pressure.
- Increase salt intake.
- Avoid all types of alcoholic beverages.
- Always cross your legs while sitting.
- Drink water to prevent dehydration-induced hypotension.
- Eat small meals within frequent intervals.
- Wear compression stockings.
- Avoid sudden position changes to prevent orthostatic hypotension.
Yes, a hot shower can reduce your blood pressure. Certain studies have mentioned that having a warm bath can decrease hypertension and heart rate. But, it has only minimal benefits; those with severe hypertension will always need proper medical treatment to avoid complications.
A routine ten minutes of brisk or moderate walking at least three times a day lowers blood pressure by decreasing blood vessel stiffness. It ensures that blood can flow more easily through the stiff vessels. The effects of walking are most noticeable during the course as well as immediately after a walking activity.
Low blood pressure is known as hypotension. It can occur to anyone due to many causes. As a person ages, there is a normal physiological decrease in blood pressure, especially on standing and after eating. It occurs mainly in adults older than 65.
Low blood pressure occurs when blood pressure is much lower than the average level for the person’s age. This means that the vital organs and other parts of the body are not getting enough volume of blood. The normal adult blood pressure is mostly between 90/60 mmHg and 120/80 mmHg.
When you experience certain red flag symptoms of low blood pressure, it is necessary for you to rush to the emergency room. Those symptoms include dizziness, shortness of breath, and fainting.
When you have a sudden episode of low blood pressure, you need to drink caffeine or lime juice immediately. Eating chocolate will also help. These drinks are highly capable of increasing blood pressure immediately.
The following are the side effects of blood pressure medications.
- Diarrhea or constipation.
- Dizziness or lightheadedness.
- Erection problems.
- Feeling nervous.
- Feeling of tiredness or lack of energy.
- Nausea or vomiting.
Yes, most of the symptoms caused by low blood pressure make the person look weak and tired. Young adults with low blood pressure might experience difficulty in handling their routine activities. In older adults, low blood pressure could be severe enough to resist them even from standing.
Orthostatic hypotension is also known as postural hypotension. It is a type of low blood pressure that occurs when a person stands up from a sitting position or lying down. Orthostatic hypotension can make the affected person feel very dizzy or lightheaded, and may even cause the person to faint.
Blood pressure is the force at which the blood is pushed against the walls of the human arterial walls as the heart pumps blood. The average adult blood pressure is 120/80 mmHg. When a person’s blood pressure falls below this range, it is known as hypotension.
Last reviewed at:
14 Oct 2019 - 5 min read
MBBS, Calcutta University, Diploma In Tropical Medicine and Hygiene from School of Tropical Medicine,Calcutta University, Diploma In Cardiology, Calcutta University, Post Graduate Diploma In Preventive and Promotive Healthcare
Query: Hello doctor, I have an automatic device for checking blood pressure at home. There are 3 options of which first says "sys", the second one says "dia" and the third one "pulse'. Which option is for checking the blood pressure and how much should is normal? Read Full »
Query: Hi doctor, I am a 56 year old male. I am on BP medicine Cresar 40 since a month. Prior to that, I was on Aten 50. Now, my BP is around 130/100 mmHg and before it was 160/106 mmHg. When I take my walk or I am standing I feel giddy, probably for less than a second. It is more prevalent when I turn my... Read Full »
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