What is low blood pressure? Symptoms, causes and prevention

Low blood pressure, also called hypotension, can be an unpleasant experience and can be caused by a lot of different factors. In fact, while low blood pressure can be symptomless for some, it can cause symptoms such as dizziness, fainting, and can even be life-threatening in extreme cases. This guide covers the symptoms of low blood pressure to look out for, the main causes and how to lower your blood pressure.

What is low blood pressure?

Low blood pressure is blood pressure that has lowered to an unhealthy amount for an extended period. Abnormally low blood pressure is often called hypotension. There are several types of hypotension, including:

  • Postural (or orthostatic) hypotension: sudden drop in blood pressure when standing up from sitting or lying down.
  • Postprandial hypotension: drop in blood pressure one or two hours after having a meal.
  • Neurally mediated hypotension: drop in blood pressure after standing for a long period of time.
  • multiple system atrophy with orthostatic hypotension: drop in blood pressure due to nervous system damage.

How can I measure my blood pressure?

Your blood pressure can be measured by using an instrument called a sphygmomanometer, which has an inflatable cuff that’s placed around one arm. The inflation increases the pressure on the arm, allowing the machine to get an accurate blood pressure reading.

A blood pressure reading is shown using two measurements:

  • The systolic pressure (the higher reading), which measures the force of blood being pumped around the blood vessels when your heart contracts.
  • The diastolic pressure (the lower reading), which measures the resistance to the blood flow in the blood vessels, or rather when the heart relaxes between beats.

Once measured, two numbers representing these measurements will show up on the sphygmomanometer screen. The higher number is the systolic pressure and the lower number is the diastolic pressure. You’ll also see that the measurement is in mmHg, which means millimetres of mercury, and denotes a unit of pressure.

Normal blood pressure is considered to be between 90/60mmHg and 120/80mmHg. High blood pressure is any number above 140/90mmHg.

What are the symptoms of low blood pressure?

Low blood pressure can be symptomless. However, people with low blood pressure can experience some of the following symptoms:

  • Headaches
  • Nausea
  • Dehydration
  • Blurred vision
  • Tiredness
  • Lack of concentration
  • Fainting and dizziness
  • Cold and clammy skin

Is low blood pressure normal in pregnancy?

The changes that happen to a person’s body during pregnancy can affect their blood pressure as the body is working hard to pump blood to both the mother and baby. Therefore, checking your blood pressure during pregnancy is important. Nevertheless, the potential symptoms of low blood pressure during pregnancy are the same.

What are the causes of low blood pressure?

Your blood pressure typically varies throughout the day depending on your body position, stress levels, breathing rhythm, medications taken, and the time of day. However, certain medical conditions can also cause low blood pressure. These include:

  • Heart problems such as heart attacks, heart failure, heart valve problems and bradycardia (very low heart rate)
  • Endocrine problems such as pathyroid disease, Addison’s disease, hypoglycaemia and diabetes.
  • Dehydration
  • Loss of blood through trauma, major surgeries and injuries.
  • Serious infections such as septicemia
  • Severe allergic reaction (anaphylaxis)
  • Lack of nutrients such as vitamin B12, folate and iron in your diet
  • Pregnancy
  • Medications such as alpha blockers, beta blockers, diuretics and anti-depressants

How to treat low blood pressure?

Low blood pressure that doesn’t present signs or symptoms (or only mild symptoms) does not usually require treatment. However, if you have persistent symptoms, your GP will be able to establish the correct course of treatment pressure depending on the cause.

The treatments may include:

  • Drinking water to avoid dehydration
  • Wearing compression stocking to aid blood flow
  • Taking vitamin B12, folate and iron supplements
  • Reducing meal sizes
  • Reducing stress levels with relaxing activities

For causes that are medically related, such as heart problems, there will be tailored solutions or preventative measures.

What does it mean if you have naturally low blood pressure?

Having naturally low blood pressure isn’t necessarily a bad thing and can in fact lower your risk of heart disease and stroke. However, if your blood pressure becomes dangerously low regularly, causing you to become dizzy or faint, then you should see your GP.

What is the best medicine for low blood pressure?

There are various medicines for treating different types of low blood pressure and the medicine you will be given is dependent on the cause. However, the most common medicines used to treat low blood pressure include Fludrocortisone and Midodrine. Medicine treatments are only usually used in severe cases of low blood pressure as this condition can usually be treated simply.

How can I get my blood pressure tested?

If you want to check your blood pressure, you can get it measured as part of a health assessment with Bluecrest Wellness. As well as blood pressure, we’ll also perform an ECG, lung test and biometric analysis to check various aspects of your health. Our health checks consist of in-depth, face-to-face health checks with one of our Health Assessment Specialists, which you can easily book online at one of over 2,000 mobile clinics available nationwide. You will receive a wide array of other key health markers and a detailed results report sent through the post.