Low Blood Pressure (Hypotension)
Medically reviewed and updated by: Hussain Abdeh MPharm: 2211840
Updated on: 15/06/2021
Blood pressure refers to the pressure in your blood as it travels through your arteries. You need an adequate amount of pressure for blood to successfully circulate around your body, so having low blood pressure can cause a range of health issues.
In this article, we will take a look at what exactly low blood pressure is, what causes it and what can be done to treat it.
What is low blood pressure?
Low blood pressure, or hypotension, is categorised as a blood pressure that is lower than 90/60mmHg. An ideal blood pressure is normally considered to be between 90/60mmHg and 120/80 mmHg.
When blood pressure becomes low, the heart starts working harder to try and pump blood around the body more effectively. At the same time, blood vessels around the body will constrict to try and prevent the blood’s pressure from dropping any lower.
For a simpler explanation on what the numbers mean, we recommend looking at this helpful blood pressure chart.
Causes of low blood pressure
Hypotension can be caused by a range of different factors. They can include:
- Blood loss
- Medical emergencies, such as anaphylactic or septic shock
- Medical conditions, particularly those which affect the heart, kidneys and/or endocrine system
- Infections in the bloodstream
- Endocrine disorders like diabetes, thyroid disease or adrenal insufficiency
If you are taking certain medicines, these may also cause your blood pressure to drop. The most common offending medicines for lowering blood pressure include:
- Erectile dysfunction medicines
- Tricyclic antidepressants
Sometimes, you may develop low blood pressure for no reason at all. This is known as chronic asymptomatic hypotension and is not normally harmful and does not usually require any intervention.
Low blood pressure symptoms
The symptoms of low blood pressure can vary from person to person. However, the most common symptoms of hypotension include feeling dizzy or weak and feeling nauseous. In addition to this, people may experience the following symptoms when they have low blood pressure:
• Blurred vision
• Passing out or fainting
• Difficulty concentrating
The symptoms you experience may correlate with how low your blood pressure drops. Slightly low blood pressure may cause no noticeable symptoms, while severely low blood pressure may result in fainting, dizziness and blurred vision.
Although the symptoms of low blood pressure can occur at any time, some people may experience noticeable symptoms when they stand up. This is known as postural hypotension.
Alternatively, the symptoms of low blood pressure may become apparent after you have eaten a meal. This is due to the increased blood flow to your digestive system reducing blood flow to other parts of your body.
For some people, having a slightly low blood pressure seems to be their body’s natural functioning levels. Providing they are not experiencing any adverse symptoms and their hypotension isn’t caused by an underlying health problem, doctors may be satisfied that the issue does not constitute a medical problem.
However, it is important to identify the cause of low blood pressure in order to assess whether intervention or treatment is necessary, regardless of whether the patient is symptomatic or not.
Although hypotension can occur without any noticeable symptoms, blood pressure that is excessively low can cause various serious health issues. Due to this, it’s important to seek medical advice if you experience a period of acute hypotension, symptoms associated with low blood pressure or chronically low blood pressure.
Low blood pressure treatments
If your blood pressure is lower than average but it does not lead you to experience any symptoms and does not appear to be caused by an unrelated health issue, your doctor may decide that no treatment is necessary.
However, many people who are diagnosed with hypotension do require medical treatment. In most instances, the appropriate treatment will depend on the cause of hypotension, the severity of the condition and the symptoms the patient is experiencing.
The typical first line of treatment for low blood pressure is making changes to your lifestyle. Drinking more fluids can help to increase your blood pressure, so doctors may advise you to consume more water if you are experiencing symptoms as a result of hypotension.
In addition, sitting or lying down with your legs raised can help your blood to circulate more easily and can increase your blood pressure.
They may also suggest:
- Eating smaller meals more frequently, as well as lying or sitting down for a while after eating
- Getting up slowly when you wish to stand up
- Raising the head of your bed by about 15cm
- Not sitting down for long periods of time
- Not changing your posture suddenly, such as bending down quickly
- Not drinking caffeinated drinks (such as tea and coffee) in the evening
- Cutting down how much alcohol you drink
If hypotension occurs as a side effect of taking medication for an unrelated condition, your doctor may alter your dose or switch you to another type of medicine. However, you should consult a physician before changing any medication you’re taking.
If you continue to experience low blood pressure despite making changes to your lifestyle, your doctor may prescribe medication to increase it. Common medications used to treat hypotension include:
• Beta-agonists or alpha-agonists
Taking care of your blood pressure
Maintaining healthy blood pressure is important because of the health risks hypotension and hypertension (high blood pressure) present. As your blood pressure is dependent on the functionality of your heart and blood vessels, it’s important to modify your lifestyle habits to prevent damage occurring.
Smoking, obesity and a build-up of plaque in the arteries can all affect blood flow within the vessels, as well as heart function. Similarly, poor circulation may make it harder for blood to flow around the body and could lead to low blood pressure.
For men who have been diagnosed with low blood pressure, it is essential that they do not take any sexual performance medication, such as viagra that is used to treat erectile dysfunction. This is because the active ingredient, sildenafil, can cause low blood pressure.
Although high blood pressure is often caused by poor lifestyle choices, the causes of low blood pressure can be more varied. Due to this, patients may find it difficult to remedy severe hypotension without medical intervention and treatment.