Low blood pressure

At HCA UK, we offer tests, treatment and advice to improve your condition. 

• Ranked No. 1 in the UK for private cardiovascular care, treating more than 26,000 people per year
• Appointments with a consultant specialising in low blood pressure symptoms and treatment confirmed within 24 hours
• Multi-disciplinary teams recommended to friends and family by 99% of patients

Seek emergency medical care if you or someone you know experience the following, which may be symptoms of shock:

• Fast, shallow breathing
• A weak yet rapid pulse
• Pale, cold and clammy skin

If you see any of these signs, call 999 immediately.

What is low blood pressure?

Your blood pressure measures the strength that your heart pumps blood around your body. It is measured in millimetres of mercury (mmHg) and represented by two numbers:

• Systolic pressure: The top number; this measures the pressure when your heart beats and moves blood through your arteries.
• Diastolic pressure: The lower number; this measures the pressure in your arteries when your heart is at rest.

Anything below 90/60mmHg (your doctor or nurse will say "90 over 60") is classed as low blood pressure. However, a low blood pressure reading does not necessarily mean you are unwell and may not result in you experiencing any symptoms.

A lower blood pressure has even been shown to lead to better health in old age.

Low blood pressure vs high blood pressure

An ideal blood pressure is classed as anything between 90/60mmHg and 140/90mmHg. Anything above the latter reading is high blood pressure.

High blood pressure is more common and linked to lifestyle factors like your weight and diet or smoking. It can increase your risk of developing heart failure and coronary artery disease or having a stroke.

How to check if you have low blood pressure

You can have a blood pressure reading taken by your GP, while some pharmacies also offer appointments. Your reading will be taken by a doctor or nurse using a blood pressure monitor.

Blood pressure monitors are also available for you to buy if you want to take readings at home. Blood Pressure UK's website includes lots of useful information if you are self-testing.

What causes low blood pressure?

Some people live completely healthy lives with a blood pressure that would be classed as hypotension. The time of day, your mood and eating meals can all lower your blood pressure in completely natural ways.

You would only be recommended to undergo treatment for low blood pressure if it results in symptoms. With HCA UK, you’re in the best hands when it comes to explaining and testing the causes of low blood pressure.

Some common reasons for low blood pressure developing include:

• Pregnancy: In the first two trimesters of pregnancy, blood vessels expand to increase the supply to the uterus. This naturally results in blood pressure decreasing. It may result in symptoms such as fatigue but is typically nothing to worry about. Blood pressure tests will be done at all prenatal appointments during pregnancy.
• Blood loss: Severe injuries or internal bleeding can result in you losing large amounts of blood volume, with the pressure falling as a result.
• Changes in position: Experiencing symptoms when standing up quickly from a seated position or lying down is known as orthostatic hypotension. If you're still, blood collects in your legs and abdomen and there is less than is required in your system when you suddenly move. Brief periods of light-headedness and dizziness are common but should pass quickly.
• Allergies: The body's natural reaction to allergies includes blood vessels widening, which can cause blood pressure to drop. If blood pressure drops too much, the body can go into anaphylactic shock.
• Diet: If you regularly eat foods low in nutritional value, lacking Vitamin B12, folate and salt, it may lead to low blood pressure.
• Dehydration: If your body is not properly hydrated, that can decrease the volume of blood in the body and consequently affect your blood pressure.

Conditions associated with low blood pressure

You may experience low blood pressure if you have another underlying condition.

• Bradycardia: An abnormally slow heart rhythm (arrhythmia). If your heart rate is too slow, a lack of blood in your system can lead to a decrease in pressure.
• Heart failure: If your heart muscle is stiff or beating weakly, it may not pump enough blood around your system.
• Diabetes: Although diabetes is more commonly associated with high blood pressure, medication and dehydration caused by the condition can result in blood pressure being classed as low.
• Sepsis: This is a serious condition that arises from the body reacting abnormally to an infection. Septic shock is when the reaction causes a severe loss of blood pressure.
• Parkinson's disease: Low blood pressure can be a symptom of Parkinson's or experienced as a result of medication used to treat the condition.

Possible complications of low blood pressure

• Shock: If your blood pressure drops too quickly or by too much, your body can go into shock. If this happens, your vital organs lack the necessary supply of oxygen and can start to shut down. This is a potentially life-threatening condition and requires emergency care.
• Falls: If you feel dizzy and light-headed or faint because of low blood pressure, you are at greater risk of losing your balance and falling over. This could result in bumps, bruises and cuts or even broken bones and concussion in more serious circumstances.
• Heart issues: If you have low blood pressure, it may mean that your heart beats faster and harder to try and compensate. This can increase your risk of heart failure, coronary artery disease and stroke.

How is low blood pressure diagnosed?

Low blood pressure can only be properly diagnosed with a blood pressure monitor.

An inflatable cuff will typically be attached to your arm and filled with air until it is tight. This can be slightly uncomfortable but will only be in place for a short period. Sensors in the cuff then provide a reading, usually on a digital display, so you have instant results. 

Depending on your reading and what symptoms you're experiencing, you may also be recommended to undergo further tests to determine underlying conditions or to understand your blood pressure better:

• Ambulatory blood pressure monitoring: Also known as 24-hour blood pressure monitoring, this helps to monitor if and how your blood pressure fluctuates throughout the day. It can also be a good alternative if being in a hospital environment affects your blood pressure.
• Tilt-table test: This may be recommended if you have experienced dizziness or light-headedness. You will be strapped to a bed that is slowly tilted, head up, to a 60-degree angle. Your blood pressure will be monitored throughout to see if and how it reacts.

What are the treatment options for low blood pressure?

Treatment for low blood pressure will depend on your symptoms, overall health or any underlying cause. Your GP or consultant will talk to you about your condition and explain the best approach for you.

Natural ways to increase blood pressure

• Eating small, healthy meals frequently throughout the day
• Choosing foods high in Vitamin B12 and folate, such as eggs, meat and leafy greens
• Salty food can increase your blood pressure
• Staying well hydrated, especially when exercising
• Compression stockings may help to improve your circulation and blood pressure
• Standing up or getting out of bed slowly can reduce symptoms of low blood pressure

Low blood pressure medication

Your consultant may suggest changes to your existing medication if this is likely to be contributing to your low blood pressure. It's unlikely that you would be prescribed medication to treat low blood pressure specifically. However, some may help to treat underlying causes.

• Fludrocortisone: This steroid helps your kidneys retain more salt and water, increasing blood volume as a result and lifting your blood pressure.
• Midodrine: This medication can be used to treat symptoms such as dizziness when going from sitting to standing. It works by stimulating nerve endings in your blood vessels, causing them to tighten and your blood pressure to rise. 

Low blood pressure surgery

Low blood pressure is a not-uncommon side-effect of surgery. Anaesthetic, blood loss and being prone for extended periods can reduce your blood pressure.

Surgical treatment for low blood pressure is rarely considered, unless it is to treat a different cause that has led to a decrease, such as heart failure or coronary heart disease.