Low blood pressure (hypotension) occurs when blood pressure levels drop below what is considered normal, typically below 90/60 mmHg. While it can be harmless for some people, it may cause symptoms such as dizziness, fainting or fatigue. Common causes include dehydration, medication side effects and underlying health conditions, and treatment depends on the underlying cause.
Do you ever feel dizzy when you stand up too quickly or notice a wave of fatigue that comes out of nowhere? Episodes like this are often linked to changes in blood pressure and they can happen to people at any stage of life.
Low blood pressure is quite common and for many people, it’s nothing to worry about. But in some cases, it can leave you feeling faint, tired or unwell. Knowing what’s normal, what’s not and when to act can make all the difference.
To help break it down, we asked Monique Vincent, Clinical Advisor at nib, what low blood pressure means, what might be behind it and what you can do about it.
What is low blood pressure?
Low blood pressure, also known as hypotension, happens when your blood pressure is lower than what is considered normal. Some people have naturally low blood pressure and experience no symptoms, while others may develop symptoms if blood flow to the body's organs is reduced.
Blood pressure measures the force of blood pushing against your artery walls. When it’s too low, your organs and tissues may not get enough blood flow.
It helps to think of low blood pressure in two ways. For some people, it’s simply their normal. This is often called naturally low blood pressure and it causes no symptoms and no harm. It tends to be more common in healthy, younger and physically active people, and usually needs no treatment at all.
Symptomatic low blood pressure is different. This is when your reading drops enough, or suddenly enough, to cause symptoms like dizziness, fainting, blurred vision or fatigue. It can point to something worth looking into, such as dehydration, a medication side effect or an underlying condition.
“The key difference is how you feel,” says Monique. “Naturally low blood pressure sits quietly in the background, while symptomatic low blood pressure makes itself known and may need a closer look.”
What is considered normal vs low blood pressure?
Blood pressure naturally varies from person to person. Your age, general health and even the time of day can affect your reading.
As a general guide:
Category | Blood pressure reading |
Normal | Around 120/80 mmHg |
Low | Below 90/60 mmHg |
“A single low reading doesn’t always mean there’s a problem. The key is how you feel and whether it’s a pattern,” Monique says.
What are the symptoms of low blood pressure?
Low blood pressure doesn’t always cause symptoms, but if it does, you might experience:
Dizziness or light-headedness
Fainting
Blurred or fading vision
Fatigue or weakness
Nausea.
“The tricky part is these symptoms can overlap with other conditions,” explains Monique. “That’s why it’s important to look at the bigger picture, not just one symptom on its own.”
What causes low blood pressure?
There are a few different reasons your blood pressure might drop. Sometimes it’s temporary and other times, it’s linked to an underlying condition.
Dehydration, which can happen if you're not drinking enough fluids or you've lost fluids through vomiting, diarrhoea or excessive sweating.
Standing up too quickly, which can cause a sudden drop in blood pressure known as postural (orthostatic) hypotension.
Certain medicines, including some treatments for high blood pressure, heart conditions, depression and Parkinson's disease.
Pregnancy, particularly during the first and second trimesters.
Heart conditions that affect the heart's ability to pump blood effectively.
Hormonal or endocrine disorders, such as an underactive thyroid or adrenal gland problems.
Significant blood loss from an injury or internal bleeding.
Severe infections or allergic reactions, which can sometimes cause a dangerous drop in blood pressure.
Is low blood pressure dangerous?
In most cases, low blood pressure isn’t dangerous, especially if you feel well. Plenty of people go about their day with naturally low readings and never notice a thing. It becomes more of a concern when symptoms stick around or start getting in the way of everyday life, like if the room spins every time you get up off the couch. These moments matter because they can raise your risk of falls or fainting, which are recognised complications of ongoing low blood pressure.
“It sounds alarming, but many people live with naturally low blood pressure without problems,” says Monique. “The focus is really on symptoms and overall health.”
When should you see a doctor?
It’s a good idea to speak with a GP if you notice:
Frequent dizziness or fainting
A sudden drop in blood pressure
Symptoms that affect your daily life
Symptoms alongside another health condition.
If you’re not sure whether to get checked, a telehealth appointment can be an easy first step. You can talk through your symptoms with a medical doctor or nurse practitioner from home and, if they think you need a test or a closer look, they’ll point you towards an in-person visit.
How is low blood pressure treated?
Treatment for low blood pressure depends on what’s causing it. Management often focuses on addressing the underlying issue. Your GP might recommend:
Drinking more fluids
Adjusting medications
Treating any underlying condition.
“There’s no one-size-fits-all treatment,” explains Monique. “Often, simple changes can make a noticeable difference.”
How can you manage low blood pressure day-to-day?
For mild or occasional symptoms, small lifestyle changes can help you feel better. Monique says some options can include:
Drinking enough water throughout the day
Standing up slowly, especially first thing in the morning
Eating smaller, regular meals
Paying attention to how your body responds.
Keeping track of your symptoms in a journal or diary can also help you and your GP identify patterns. Low blood pressure can be confusing, especially when symptoms come and go. In many cases, it’s harmless. But if something doesn’t feel right, it can be worth getting checked out by a GP. Making sure you’ve booked in regular health checks can also help you stay on top of changes and spot potential issues early.
FAQs about low blood pressure
What causes low blood pressure suddenly?
A sudden dip is often triggered by everyday factors like dehydration, standing up too quickly, hot weather or standing for long periods. Some medications can also cause it. A sharp, sudden drop paired with feeling very unwell can signal a serious infection, which needs urgent medical care.
Can dehydration cause low blood pressure?
Yes. Dehydration is one of the most common causes of low blood pressure. When your body is low on fluids, there’s less blood to circulate, which can lower your reading and leave you feeling dizzy or light-headed.
What should you do if your blood pressure is low?
If you feel well, low blood pressure often needs no action. For mild symptoms, it can help to drink enough water, stand up slowly, eat smaller regular meals and notice how your body responds. See a GP if you have frequent dizziness or fainting, a sudden drop, or symptoms that affect your daily life.
Is low blood pressure normal for some people?
Yes. For many people, naturally low blood pressure is simply their normal and causes no symptoms or harm. It’s more common in healthy, younger and physically active people, and usually needs no treatment. What matters most is how you feel.
What if I have symptoms but my blood pressure is normal?
Symptoms such as dizziness, light-headedness, fainting, fatigue or a racing heart don't always mean you have low blood pressure. Some conditions can cause similar symptoms even when your blood pressure is normal. For example, postural orthostatic tachycardia syndrome (POTS) affects how the body responds to standing and can cause dizziness, palpitations and fainting without consistently low blood pressure. If you're experiencing these symptoms, especially if they're ongoing, worsening or affecting your daily activities, it's important to see your GP for assessment.
Still not sure if it's worth getting checked? A telehealth appointment is an easy first step so you can talk through your symptoms with a doctor or nurse practitioner from home. If something doesn't feel right, you can always use our find a provider tool to search for a GP near you and get checked out in person.
The information on this page is general information and should not be used to diagnose or treat a health problem or disease. Do not use the information found on this page as a substitute for professional health care advice. Any information you find on this page or on external sites which are linked to on this page should be verified with your professional healthcare provider.
