What To Do When Blood Pressure Is Low?

Overview

Blood pressure is the amount of force by which blood pushes against the walls of your arteries as your heart beats and blood flows through them.

Low blood pressure is also known as hypotension; not to be confused with hypertension, which is high blood pressure. Hypotension is defined as a blood pressure reading of less than 90/60mmHg. This number may not make sense to those without medical knowledge; in layman’s terms, the first of these two numbers (90, in this case) is the highest level your blood pressure reaches and is known as systolic pressure; this is the pressure when your heart contracts. The second number (in this case 60) is your blood pressure at its lowest when your heart relaxes; this is known as diastolic pressure.¹ 

Though the symptoms of hypotension may be unpleasant or inconvenient, having low blood pressure is not a very serious condition in most cases. It only becomes dangerous if the pressure that blood is pumped it is not enough to reach the vital organs in the body.⁵ Of course, if you are concerned about having low blood pressure, are in pain, or it is getting in the way of your everyday life, then it is best to seek out a doctor to discuss your symptoms and make sure that nothing serious is going on, or simply to ease your discomfort. 

This article is intended to inform you of the symptoms of low blood pressure, the possible causes, different types of hypotension, and how you can use simple strategies at home to prevent it.

Causes of low blood pressure

Blood pressure naturally varies depending on the time of day. It decreases greatly at night during rest, then sharply increases in the morning, peaking in the late afternoon, according to the body’s circadian rhythm, or ‘body clock’.⁷ You therefore may be more likely to experience low blood pressure in the morning due to your body’s natural rhythms. 

Similar to this, many other causes of hypotension are just as normal. Low blood pressure can be inherited from parents or maybe because you are fit and healthy. It can also be developed later in life, as you get older, and is more common in elderly people. 

However, low blood pressure can also be caused by pregnancy or conditions such as diabetes, as well as some medicines.¹ Beta-blockers and calcium channel blockers are types of medication that can lead to hypotension, whilst diuretics may also have the same effect. Losing a large amount of blood due to injury or trauma can also lead to hypotension.⁵ 

In addition to this, arrhythmias may cause low blood pressure; this is where the heart has an abnormal beat/rhythm, which can cause hypotension. Valvular stenosis and valvular regurgitation are both cases of the valves of the heart not working properly, meaning blood is not correctly pumped through the heart, which also leads to low blood pressure. Diastolic or systolic heart failure involves the chambers in the heart not being able to fill or contract properly, and has the same effect, as cardiac tamponade, which is when extra fluid or blood builds up around the heart.⁵ These conditions are much less common, however, it can only help to be aware of them. 

When do you think blood pressure is low?

Symptoms of low blood pressure

Symptoms of low blood pressure include feeling sick, lightheadedness, blurred vision, dizziness, and feeling faint.¹ Loss of consciousness may occur in more severe cases. Less specific symptoms may include shoulder and neck pain, headache, leg buckling, confusion, trouble concentrating, general weakness, and tiredness.⁸

Types of low blood pressure

There are different types of hypotension, stemming from different causes. This means symptoms may slightly vary but are generally similar.

Postural hypotension (also known as orthostatic hypotension) is where you experience the symptoms of low blood pressure when you stand up suddenly or change position.¹ Causes may include dehydration, pregnancy, long-term bed rest, or certain medicines (such as diuretics, anti-Parkinson’s medications, or drugs to reduce high blood pressure). The likelihood of experiencing this type of low blood pressure increases as you get older, and it is therefore common in elderly people.²

Postprandial hypotension is a drop in blood pressure that happens within 2 hours after eating a meal. It occurs often in people who have conditions such as type 2 diabetes or Parkinson’s disease, however, it is also common in healthy older people.³

Neurally mediated hypotension is also known as neurally mediated syncope; syncope is a temporary loss of consciousness which is caused by a fall in blood pressure. This occurs more commonly in young adults and children and happens after standing for long periods of time.⁴

Whilst these are relatively minor problems, there are many more complex types of low blood pressure which are life-threatening, though these are easily distinguishable from the more mild cases of hypotension described above. For example, distributive shock is associated with anaphylactic allergic reactions and septic shock (when your blood pressure drops dangerously low after an infection). Cardiogenic shock occurs when the heart cannot pump enough blood/oxygen to the brain and vital organs. Hypovolemic shock is possible in cases of massive loss of blood due to injury or overusing diuretic medication. Obstructive shock is where the blood vessels are obstructed or compressed so that blood flow does not occur effectively. People may also suffer from a combination of any number of the above.⁵

Prevention and medication

Lifestyle changes or treating the cause of hypotension are usually sufficient to increase blood pressure, hence medication is rarely needed. At home, you can help your hypotension by eating small, frequent meals, increasing the amount of water you drink, moving slowly from lying to sitting to standing, and sitting still for a while after eating. Avoid caffeinated drinks at night, drinking too much alcohol and sitting, or standing for long periods.¹

If these more simple measures do not help then there may be an underlying cause of your low blood pressure. ECG and chest X-ray may be used to help diagnose the cause of your low blood pressure. The doctor may ask that you stop taking your medication or alter the dose.⁵ They may also recommend that you wear support stockings, which can increase blood pressure and improve circulation.¹

When to see a doctor?

If you keep experiencing the symptoms of low blood pressure, particularly dizziness and fainting, then your blood pressure needs to bechecked by a doctor, practice nurse, or pharmacist.¹ There are also blood pressure monitors that can be used at home.

The NHS recommends that you should have a blood pressure check by a medical professional at least once every 5 years if you are between the ages of 40-74, and offers this test for free once you reach that age.¹ The test will check if your blood pressure is too high or too low, and will inform the doctor if you need any treatment. As mentioned before, low blood pressure is not normally very serious, however high blood pressure can be dangerous as it can increase your risk of serious issues such as heart attacks and strokes if left untreated.⁶

Summary

In summary, most cases of low blood pressure are not serious and can be treated by simple lifestyle changes. Sometimes it will take changing the medication you are on or changing the dose, however, this should be decided by a doctor. It is important to check your blood pressure once you reach a certain age, to make sure it is not too high or too low. Even if you think your symptoms may be minor, if you are concerned that you have low blood pressure then it is best to see a doctor, even if it is just for peace of mind.