Low Blood Pressure (Hypotension): Numbers, Symptoms, Causes, and When It Needs Treatment
Updated: 3 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Low blood pressure (hypotension) is generally a reading below 90/60 mm Hg. It often causes no symptoms, but it can cause dizziness, fainting, and blurry vision. Four types exist, including orthostatic hypotension (a drop when standing) and postprandial hypotension (a drop after eating). Causes range from dehydration and pregnancy to blood loss, severe infection, and certain medicines. Treatment depends on the cause and can include more water, more salt (with medical approval), compression stockings, position changes, and specific medicines [1][2].
Quick Answer: What is low blood pressure?
Low blood pressure, or hypotension, is a reading below 90/60 mm Hg. It often causes no symptoms and needs no treatment, but it can cause dizziness, lightheadedness, fainting and blurry vision. Causes include dehydration, blood loss, heart problems and certain medicines. Fainting or shock symptoms are a medical emergency. Treatment targets the cause. [1] [2]
What the research says
Orthostatic hypotension is linked to falls in older adults. A meta-analysis of 50 studies (49,164 people) found that orthostatic hypotension was associated with falls (odds ratio 1.73, 95% CI 1.50–1.99), and the result held regardless of study design, study quality, or how orthostatic hypotension was defined (Mol et al., J Am Med Dir Assoc, 2019 [3]).
Postprandial hypotension is common in older adults. A meta-analysis of 13 studies including 3,021 older adults estimated a prevalence of 40.5% (95% CI 29.0%–51.9%), higher in hospital geriatrics departments (49.3%) than in the community (32.8%); results varied widely between studies, and the authors call for international diagnostic criteria (Huang et al., Age Ageing, 2024 [4]).
Orthostatic hypotension is associated with a higher risk of cognitive problems. A systematic review and meta-analysis of longitudinal studies (15 met the inclusion criteria) found that people with orthostatic hypotension at baseline had a 28% greater risk of cognitive impairment (odds ratio 1.28, 95% CI 1.16–1.41) and a 27% greater risk of incident dementia (hazard ratio 1.27, 95% CI 1.16–1.39) (Duval et al., Maturitas, 2024 [5]).
What Is Low Blood Pressure?
Low blood pressure is a condition in which the force of the blood pushing against the artery walls is too low. The medical term for it is hypotension [1].
Blood pressure is measured in millimeters of mercury, written as mm Hg. In general, low blood pressure is a reading lower than 90/60 mm Hg. Healthy blood pressure is considered normal when it is lower than 120/80 mm Hg [1].
One important point often surprises people: what counts as low blood pressure for one person might be perfectly fine for someone else. Hypotension might cause no symptoms that you notice, or it might cause dizziness and fainting. In some cases, low blood pressure can be life-threatening. The causes include dehydration and other serious medical conditions, so it matters to find out what is causing low blood pressure so it can be treated if needed [1].
Key distinction: Low blood pressure is only considered a medical problem when it causes symptoms. A person who frequently has low readings but feels fine usually does not need treatment and simply has it tracked at routine checkups.
How Blood Pressure Works
Blood pressure is determined by two factors working together [1]:
Factor | What it means |
Amount of blood the heart pumps | More pumped blood means more force against the artery walls. |
Resistance to blood flow in the arteries | Narrower or stiffer arteries create more resistance; wider arteries create less. |
A blood pressure reading has two numbers:
Number | Name | What it measures |
Top number | Systolic pressure | The pressure in the arteries when the heart beats. |
Bottom number | Diastolic pressure | The pressure in the arteries when the heart rests between beats. |
Blood pressure is not fixed. It varies throughout the day depending on body position, breathing, food and drink, medicines, physical condition, stress, and time of day. It is usually lowest at night and rises sharply on waking [1].
The Four Types of Low Blood Pressure
There are four main types of hypotension, and they affect different groups of people [1]:
Type | What happens | Who it mostly affects |
Orthostatic (postural) hypotension | A sudden drop in blood pressure when standing up after sitting or lying down. Causes include dehydration, long-term bed rest, pregnancy, certain medical conditions, and some medicines. | Common in older adults. |
Postprandial hypotension | A drop in blood pressure that occurs 1 to 2 hours after eating. | Most likely affects older adults, especially those with high blood pressure. |
Neurally mediated hypotension | A blood pressure drop that happens after standing for long amounts of time. It may result from a communication problem between the heart and the brain. | Mostly affects young adults and children. |
Multiple system atrophy with orthostatic hypotension | A rare condition that affects the autonomic nervous system. It is linked with having very high blood pressure while lying down. It used to be called Shy-Drager syndrome. | Rare; occurs in adults with this specific nervous system disorder. |
The autonomic nervous system is the part of the nervous system that controls automatic functions such as breathing and heart rate. Older adults with Parkinson's disease or other conditions that affect this system have a higher risk of postprandial hypotension [1].
What are the symptoms of low blood pressure?
Low blood pressure symptoms can include [1]:
Symptom | Notes |
Blurred or fading vision | Vision may dim, especially when standing up. |
Dizzy or lightheaded feelings | The most commonly reported symptom. |
Fainting | Can happen when the brain briefly gets less blood flow. |
Fatigue | A general sense of tiredness and low energy. |
Trouble concentrating | Difficulty focusing or thinking clearly. |
Upset stomach | Nausea or stomach discomfort. |
For some people, low blood pressure may be a symptom of an underlying health condition. That is especially true when blood pressure drops suddenly or when low blood pressure occurs together with symptoms.
A sudden fall in blood pressure can be dangerous. A change of just 20 mm Hg can make you feel dizzy or faint. For example, those symptoms could happen after a drop in systolic pressure from 110 mm Hg to 90 mm Hg. Big drops can be life-threatening, and can happen for reasons such as serious bleeding, serious infections, or allergic reactions [1].
Shock: The Emergency Form of Low Blood Pressure
Extreme low blood pressure can lead to a condition known as shock. Shock means the body's organs are not getting enough oxygen. Symptoms of shock include [1]:
Shock symptom | Why it happens |
Confusion, especially in older people | The brain is receiving less oxygen. |
Cold, clammy skin | Blood is pulled away from the skin to protect vital organs. |
Decreased skin color (pallor) | Less blood flow near the surface of the skin. |
Rapid, shallow breathing | The body tries to take in more oxygen. |
Weak and rapid pulse | The heart pumps faster to compensate for low pressure. |
When should you see a doctor for low blood pressure?
If you have symptoms of extreme low blood pressure or shock, call 911 or your local emergency number right away. Shock is a medical emergency [1].
Most healthcare professionals consider blood pressure to be too low only if it causes symptoms. Minor dizzy or lightheaded feelings from time to time can be caused by many things, including spending too much time in the sun or in a hot tub. It is important to see a healthcare professional to find out the cause of your symptoms.
If you often have low blood pressure readings but feel fine, you might not need treatment. Instead, your healthcare professional tracks your health during routine checkups. It can help to keep a record of your symptoms, when they occur, and what you are doing at the time [1].
Situation | What to do |
Symptoms of shock (cold clammy skin, weak rapid pulse, confusion) | Call 911 immediately. |
Frequent dizziness or fainting | See a healthcare professional to find the cause. |
Occasional mild dizziness (for example, after sun or hot tub exposure) | Mention it at your next checkup. |
Frequent low readings but no symptoms | Usually no treatment; track at routine checkups and keep a symptom log. |
What causes low blood pressure (hypotension)?
Low blood pressure has various causes. Some health conditions and the use of certain medicines can cause it. Other factors affect blood pressure as well [1].
Conditions That Can Cause Low Blood Pressure
Condition | How it lowers blood pressure |
Pregnancy | Changes during pregnancy cause blood vessels to expand fast, which may cause blood pressure to drop. Low blood pressure is common in the first 24 weeks of pregnancy. After a person gives birth, blood pressure usually returns to the level it was before pregnancy. |
Heart and heart valve conditions | A heart attack, heart failure, heart valve disease, and a slow heart rate (bradycardia) can cause low blood pressure. |
Hormone-related (endocrine) diseases | Conditions such as Addison's disease that affect glands making key hormones may cause blood pressure to drop. Low blood sugar (hypoglycemia) and diabetes may lower blood pressure too. |
Dehydration | When the body does not have enough water, the amount of blood in the body declines, which can cause blood pressure to drop. Fever, vomiting, severe diarrhea, overuse of diuretic medicines, and strenuous exercise can lead to dehydration. |
Blood loss | Losing a lot of blood reduces blood volume, leading to a severe drop in blood pressure. Causes of serious blood loss include injuries and internal bleeding. |
Severe infection | When an infection enters the bloodstream, it can lead to a life-threatening drop in blood pressure called septic shock. This spreading blood infection is also called septicemia. |
Severe allergic reaction (anaphylaxis) | Symptoms of a severe allergic reaction include a sudden and large drop in blood pressure. |
Lack of nutrients in the diet | Low levels of vitamin B-12, folate, and iron can keep the body from making enough red blood cells. This lack of healthy red blood cells is called anemia, and it can lead to low blood pressure. |
Medications That Can Cause Low Blood Pressure
Some medicines can cause low blood pressure [1]. It is never safe to change or stop these medicines on your own; talk to your healthcare professional first.
Medication group | Examples mentioned |
All blood pressure medicines | Diuretics such as furosemide (Lasix) and hydrochlorothiazide (Microzide). Alpha blockers such as prazosin (Minipress). Beta blockers such as atenolol (Tenormin) and propranolol (Inderal). |
Parkinson's disease medicines | Pramipexole (Mirapex ER) and medicines that contain levodopa. |
Tricyclic antidepressants | Doxepin (Silenor) and imipramine (Tofranil). |
Erectile dysfunction medicines | Sildenafil (Viagra) and tadalafil; they must never be taken with nitrate heart medicines such as nitroglycerin, because the combination can cause a dangerous drop in blood pressure. |
Who is at risk of low blood pressure (hypotension)?
Low blood pressure can affect anyone, though certain risk factors make hypotension more likely. Risk factors for hypotension include [1]:
Risk factor | Details |
Age | Drops in blood pressure when standing up or after eating occur mainly in adults older than 65. Neurally mediated hypotension mainly affects children and younger adults. |
Medications | Certain medicines have the potential to cause low blood pressure, including all medicines that treat high blood pressure. |
Certain diseases | Parkinson's disease, diabetes, and some heart conditions can lead to low blood pressure. |
Alcohol or illegal drugs | Either of these may raise the risk of low blood pressure. |
What complications can low blood pressure cause?
Complications of low blood pressure can include dizzy feelings, weakness, fainting, and injury from falls. Falls are a particular concern for older adults, where a fall can cause fractures and other serious harm. Severely low blood pressure can lower the body's oxygen levels, which can lead to heart and brain damage. This is why extreme drops in blood pressure, and the shock that can follow them, are treated as emergencies [1].
Complication | Severity level |
Dizzy feelings | Common; usually mild. |
Weakness | Common; usually mild to moderate. |
Fainting | Moderate; raises the risk of fall injuries. |
Injury from falls | Serious; especially dangerous for older adults. |
Heart and brain damage from low oxygen | Severe and potentially life-threatening. |
How can you prevent low blood pressure?
When low blood pressure is tied to a reversible cause, preventing it focuses on that cause. For postprandial hypotension, certain lifestyle changes might help ease symptoms: eat small, low-carbohydrate meals, drink more water, and stay away from alcohol [1]. More general prevention steps come from the lifestyle and home remedies section below: stay hydrated, limit alcohol, change positions gently, and exercise regularly while avoiding hot, humid conditions.
How is low blood pressure diagnosed?
To find out if you have low blood pressure, your healthcare professional gives you a physical exam and asks questions about your medical history. The exam includes checking your blood pressure [2].
You can also measure your blood pressure at home. Checking at home can help your healthcare professional catch blood pressure problems earlier than usual. Ask a member of your healthcare team to help you pick a blood pressure monitor, tell you how often to check your blood pressure, and explain what blood pressure numbers should prompt you to call the medical office right away [2].
One point deserves emphasis: if you get a home blood pressure reading at or just below 90/60 mm Hg, it is not always a cause for concern. Your healthcare professional might tell you that the reading is OK for you, especially if you have no symptoms [2].
Tests Used to Find the Cause
Other tests may be done to find out the cause of low blood pressure [2]:
Test | What it does |
Blood tests | Can help find symptoms of other conditions that can lower blood pressure. These include low blood sugar (hypoglycemia), high blood sugar (hyperglycemia or diabetes), and a low red blood cell count (anemia). |
Electrocardiogram (ECG or EKG) | A quick and painless test that measures the electrical activity of the heart. Electrodes are attached to the chest and sometimes to the arms or legs, and wires connect them to a machine that displays or prints results. An ECG shows how fast or slow the heart is beating and can detect a current or previous heart attack. |
Tilt table test | Studies how the body reacts to changes in position. You lie on a table that is tilted to raise the upper part of the body, which mimics the movement from lying down to standing up. Straps hold the body in place, and heart rate and blood pressure are tracked during the test. |
How is low blood pressure treated?
Low blood pressure without symptoms or with only mild symptoms rarely requires treatment [2].
If low blood pressure causes symptoms, the treatment depends on the cause. For instance, if a medicine causes low blood pressure, your healthcare professional may recommend changing or stopping the medicine, or the dose might be lowered. Never change or stop taking your medicine without first talking to your healthcare professional.
If the cause of low blood pressure is not clear or if no treatment exists, the goal is to raise blood pressure and relieve symptoms. Depending on your age, health, and the type of low blood pressure you have, there are various ways to do this [2]:
Approach | How it works | Important caution |
Use more salt | Salt and sodium can raise blood pressure, sometimes by a lot. For people with low blood pressure, that can be a good thing. | Too much salt or sodium can lead to heart failure, especially in older adults. Check with a healthcare professional before eating more salt or high-sodium foods. |
Drink more water | Fluids increase blood volume and help prevent dehydration, both of which are important in treating hypotension. | None noted. |
Wear compression stockings | These elastic stockings, also called support stockings, press on the legs and improve blood flow from the legs to the heart. | Some people have an easier time using compression belts around the stomach area, called abdominal binders, than compression stockings. |
Medicines | Fludrocortisone boosts blood volume and is often used to treat orthostatic hypotension. Midodrine (Orvaten) may be prescribed for long-term orthostatic hypotension to raise standing blood pressure levels by lessening the ability of the blood vessels to expand. | These medicines are prescribed and monitored by a healthcare professional. Midodrine carries an FDA boxed warning because it can push blood pressure too high when lying down, so it is taken during the daytime and not shortly before bed. |
What lifestyle and home remedies help with low blood pressure?
Depending on the reason for low blood pressure, the following lifestyle and home remedies might help ease or prevent symptoms [2]:
Remedy | How to do it |
Drink more water, less alcohol | Alcohol is dehydrating and can lower blood pressure, even in moderation. Water boosts the amount of blood in the body and prevents dehydration. |
Pay attention to body positions | Gently move from lying flat or squatting to a standing position. Do not sit with legs crossed. |
Leg-crossing maneuvers | If symptoms of low blood pressure begin while standing, cross the thighs like a pair of scissors and squeeze. Or put one foot on a ledge or chair and lean as far forward as you can. These moves encourage blood flow from the legs to the heart. |
Eat small, low-carb meals | To help prevent blood pressure from dropping sharply after meals, eat small meals several times a day. Limit high-carbohydrate foods such as potatoes, rice, pasta, and bread. |
Caffeine at breakfast | A healthcare professional also might recommend drinking one or two strong cups of caffeinated coffee or tea with breakfast. Caffeine can cause dehydration, though, so be sure to drink plenty of water and other fluids without caffeine. |
Exercise regularly | Work up to at least 150 minutes of moderate aerobic exercise a week, about 30 minutes of activity most days. Also aim to do strength-training exercises at least twice a week. But try not to exercise in hot, humid conditions. |
How can people cope with low blood pressure?
Living with a condition that causes occasional dizziness or fainting can be frustrating, and in some cases it means adjusting daily routines. The steps above (position changes, hydration, meal timing, and exercise habits) give you concrete actions you can control, which many people find reassuring.
Talk openly with your healthcare professional about how the symptoms affect your day, and ask about any activity restrictions that apply to you. Because some causes of low blood pressure involve the heart or the nervous system, following the recommended treatment plan and keeping follow-up appointments is one of the most important things you can do.
How should you prepare for a low blood pressure appointment?
You do not have to take any special steps to prepare to have your blood pressure checked. Do not stop taking medicines you think might affect your blood pressure without a healthcare professional's advice [2].
What You Can Do
Make a list of:
List item | What to include |
Symptoms | Include any that do not seem related to low blood pressure, and when they occur. |
Blood pressure readings | If you track your blood pressure at home, keep a log of your readings. Note multiple readings at different times of day. Also note when you have symptoms and whether they happened when your blood pressure was low. |
Important personal information | Include any family history of low blood pressure and major stresses or recent life changes. |
All medicines, vitamins, or supplements | Include the doses you take. |
Questions to ask | Bring your list of questions to your healthcare professional. |
For low blood pressure, basic questions to ask your healthcare professional include:
What is likely causing my symptoms or condition?
What are other possible causes?
What tests will I need?
What is the most appropriate treatment?
How often should I be screened for low blood pressure?
I have other health conditions. How can I best manage them together?
Are there restrictions I need to follow?
Should I see a specialist?
Are there brochures or other printed materials I can have, and what websites do you recommend?
What to Expect From Your Doctor
Your healthcare professional is likely to ask you questions, including:
Do you always have symptoms of low blood pressure, or do they come and go?
How severe are your symptoms?
What, if anything, seems to improve your symptoms?
What, if anything, appears to make your symptoms worse?
Do you have a family history of heart disease?
What is the bottom line on low blood pressure?
Low blood pressure is a common finding that is usually harmless when it causes no symptoms. A reading below 90/60 mm Hg only becomes a medical concern when it brings dizziness, fainting, blurry vision, or other symptoms, or when the drop is sudden and large. The four types of hypotension each have different patterns and different groups of people they affect, and the causes range from simple dehydration to serious heart, infection, and allergy problems [1].
If you are experiencing dizziness or fainting, the best next step is to get a proper evaluation. A healthcare professional can check your blood pressure, run the right tests to find the cause, and recommend treatment if needed, whether that is simply drinking more water, adjusting how you change positions, wearing compression stockings, or taking a prescribed medicine [2].
Your next step: If you have been feeling dizzy, faint, or unusually tired, talk to a healthcare professional about checking your blood pressure. Understanding your numbers is the first step toward feeling better, and if you ever experience signs of shock, call emergency services right away.
Frequently Asked Questions
What is considered low blood pressure?
Low blood pressure, or hypotension, is generally a reading lower than 90/60 mm Hg. However, what counts as low for one person might be fine for another. Healthcare professionals usually only consider it a problem when it causes symptoms.
Can low blood pressure cause no symptoms?
Yes. Low blood pressure might cause no symptoms that you notice, or it might cause dizziness and fainting. If you have frequent low readings but feel fine, you usually do not need treatment and will simply be tracked at routine checkups.
What are the main symptoms of low blood pressure?
Symptoms can include blurred or fading vision, dizzy or lightheaded feelings, fainting, fatigue, trouble concentrating, and upset stomach. A sudden drop of just 20 mm Hg can make you feel dizzy or faint.
What are the four types of low blood pressure?
Orthostatic (postural) hypotension is a sudden drop when standing up, common in older adults. Postprandial hypotension is a drop 1 to 2 hours after eating. Neurally mediated hypotension happens after standing for long periods, mostly in young adults and children. Multiple system atrophy with orthostatic hypotension is a rare nervous system condition.
Is low blood pressure an emergency?
Usually no, but sometimes yes. A sudden, large drop can be life-threatening. Extreme low blood pressure can lead to shock, marked by confusion, cold clammy skin, pallor, rapid shallow breathing, and a weak rapid pulse. If you have shock symptoms, call 911 or your local emergency number immediately.
What causes low blood pressure?
Common causes include dehydration, blood loss, heart and heart valve conditions, hormone-related diseases like Addison's disease, low blood sugar, diabetes, severe infection (septic shock), severe allergic reactions (anaphylaxis), anemia from low vitamin B-12, folate, or iron, and certain medicines.
Is low blood pressure common in pregnancy?
Yes. Changes during pregnancy cause blood vessels to expand fast, which may cause blood pressure to drop. Low blood pressure is common in the first 24 weeks of pregnancy and usually returns to the pre-pregnancy level after a person gives birth.
Can medicines cause low blood pressure?
Yes. All blood pressure medicines can, along with some Parkinson's disease medicines, tricyclic antidepressants such as doxepin and imipramine, and erectile dysfunction medicines such as sildenafil and tadalafil, especially when taken with nitroglycerin. Never change or stop a medicine without talking to your healthcare professional.
How is low blood pressure treated?
Low blood pressure without symptoms or with only mild symptoms rarely requires treatment. If symptoms occur, treatment depends on the cause and can include drinking more water, using more salt (with medical approval), wearing compression stockings, and medicines such as fludrocortisone or midodrine.
What lifestyle changes help low blood pressure?
Drink more water and less alcohol, move gently from lying or squatting to standing, avoid sitting with legs crossed, use leg-crossing maneuvers if symptoms start while standing, eat small low-carbohydrate meals several times a day, and exercise regularly (about 150 minutes of moderate aerobic activity per week plus strength training twice weekly), avoiding hot, humid conditions.
Related Reading
High blood pressure: the opposite end of the spectrum
Congestive heart failure: heart failure and circulation
Trusted sources to learn more:
National Heart, Lung, and Blood Institute: Low blood pressure
American Heart Association: Understanding blood pressure readings
American Heart Association: Low blood pressure: when blood pressure is too low
Arterial Line (A-Line): What It Is, Why It's Used, Placement, Risks and Aftercare explains how a thin catheter in an artery tracks blood pressure with every heartbeat, how it is placed and its risks.
Blood Pressure Measurement: How to Take an Accurate Reading and What It Means explains how to take an accurate blood pressure reading at home or in the clinic.
References
Mayo Clinic. Low blood pressure (hypotension) - Symptoms and causes. Mayo Clinic. June 13, 2024. https://www.mayoclinic.org/diseases-conditions/low-blood-pressure/symptoms-causes/syc-20355465
Mayo Clinic. Low blood pressure (hypotension) - Diagnosis and treatment. Mayo Clinic. June 13, 2024. https://www.mayoclinic.org/diseases-conditions/low-blood-pressure/diagnosis-treatment/drc-20355470
Mol A, Bui Hoang PTS, Sharmin S, et al. Orthostatic hypotension and falls in older adults: a systematic review and meta-analysis. J Am Med Dir Assoc. 2019;20(5):589-597.e5. PMID 30583909. https://doi.org/10.1016/j.jamda.2018.11.003
Huang L, Li S, Xie X, et al. Prevalence of postprandial hypotension in older adults: a systematic review and meta-analysis. Age Ageing. 2024;53(2):afae022. PMID 38411408. https://doi.org/10.1093/ageing/afae022
Duval GT, Raud E, Gohier H, et al. Orthostatic hypotension and cognitive impairment: systematic review and meta-analysis of longitudinal studies. Maturitas. 2024;185:107866. PMID 38604094. https://doi.org/10.1016/j.maturitas.2023.107866
Medical disclaimer
This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. The clinical information in this guide reflects source material last reviewed in June 2024.
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