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Low blood pressure, also known as hypotension, is widespread among people living with Postural Orthostatic Tachycardia Syndrome. While many healthy individuals, especially younger adults and athletes, naturally have low blood pressure without any issue, others may experience daily challenges because their bodies cannot maintain enough blood flow when standing upright. This guide explains why low blood pressure and PoTS often occur together, what symptoms to watch for, and how to manage them safely.
What Is Low Blood Pressure
Blood pressure is measured in millimeters of mercury, noted as mmHg, for example, 120 over 70 mmHg.
Systolic is the top number and reflects pressure when your heart beats.
Diastolic is the bottom number and reflects pressure when the heart rests.
Low blood pressure is commonly defined as a systolic reading below 90 mmHg, although in older adults, a systolic reading below 110 mmHg may be considered low.
Blood pressure and heart rate are regulated by the autonomic nervous system. This is the same system affected in PoTS, which is why both conditions often overlap.
Why Low Blood Pressure and PoTS Overlap
PoTS is an autonomic disorder in which standing causes a rise in heart rate of at least 30 beats per minute or a heart rate greater than 120 beats per minute within 10 minutes of standing.
Although the clinical definition of PoTS states that blood pressure does not drop, many people with PoTS still experience blood pressure falls during prolonged standing or tilt table testing. The same autonomic dysfunction that causes the heart rate to rise can also affect blood vessel constriction. When the blood vessels do not tighten properly the blood pressure drops and symptoms appear.
This overlapping mechanism is often seen in conditions such as Joint Hypermobility Syndrome, Chronic Fatigue Syndrome, vasovagal syncope, and other forms of orthostatic intolerance.
Symptoms of Low Blood Pressure
Some people experience no symptoms at all. Others may face significant daily limitations. Common symptoms include:
Lightheadedness
Dizziness or imbalance
Blurry vision
Fatigue
Weakness
Brain fog or cognitive slowing
Shortness of breath
Chest or back pain
Pain in the neck and shoulders when upright, also known as coat hanger pain
Fainting or near fainting
Difficulty concentrating
A sudden drop of about 50 to 60 mmHg in systolic blood pressure often leads to loss of consciousness.
Common Causes of Low Blood Pressure
Low blood pressure may be caused by a single factor or a combination of factors.
Dehydration
Low body weight
Hunger or long gaps between meals
Heat exposure
Alcohol
Over-breathing also called hyperventilation
Prolonged standing
Low fitness or deconditioning
Medications, including blood pressure medications, diuretics, tricyclic antidepressants, and medications for Parkinson’s disease
Medical conditions including Joint Hypermobility Syndrome, Diabetes, Addison’s disease, Parkinson’s disease, and autonomic failure
Types of Low Blood Pressure
Orthostatic Hypotension
This occurs when systolic blood pressure falls by at least 20 mmHg or diastolic blood pressure falls by at least 10 mmHg within three minutes of standing.
Initial Orthostatic Hypotension, often called Head Rush
This happens within the first 15 seconds of standing up quickly. It is common even in healthy individuals.
Neurally Mediated Hypotension
This results from changes in autonomic nervous system activity that cause the blood pressure to drop.
Vasovagal Syncope
This is also called reflex syncope. It occurs when a fall in blood pressure, sometimes combined with a fall in heart rate, leads to fainting.
Situational Syncope
This happens when a specific event, such as coughing, swallowing, laughing, or using the toilet, triggers a blood pressure drop.
Postprandial Hypotension
This refers to a drop in blood pressure after eating due to increased blood flow to the digestive system.
What To Do If You Feel Faint
If you feel faint, act immediately.
Sit or squat down.
If possible, lie down and elevate your legs.
Cross your thighs, engage your abdominal muscles, and make tight fists.
Rock up and down on your toes or take a few steps if you cannot sit or lie down.
Drink two glasses of water as soon as possible.
These actions help push blood back toward your heart and brain.
Learn More about: Autonomic Nervous System and Its Role in POTS
Ways To Prevent Low Blood Pressure Symptoms
Identify and treat the underlying cause whenever possible.
Drink two to three litres of fluid daily unless restricted by a doctor.
Increase fluids before getting out of bed in the morning.
Drink two glasses of water before activities that worsen symptoms.
Increase salt intake only with medical approval.
Eat smaller meals more frequently.
Avoid refined carbohydrates early in the day.
Maintain physical fitness. Exercises in a seated or lying position, such as swimming, recumbent cyclin,g and Pilates, are usually well tolerated.
Avoid prolonged standing and alcohol.
Use compression garments, including waist-high support tights or abdominal binders.
Raise the head of the bed by about ten degrees.
Get up slowly from lying or sitting.
Practice tilt training if recommended by a clinician.
Medications such as fludrocortisone or midodrine may be considered if lifestyle strategies are not enough.
PoTS and Low Blood Pressure: Understanding the Connection
The symptoms of PoTS and orthostatic hypotension can appear very similar. Many patients experience both conditions at the same time. During a tilt table test, a person with PoTS shows a significant rise in heart rate. Some also show a drop in blood pressure due to abnormalities in the autonomic nervous system.
In vasodepressor syncope, the heart rate may rise at the same time the blood pressure falls. This reactive tachycardia can appear similar to PoTS, but the underlying mechanism may differ. Treatment strategies for both often overlap.
When To Seek Medical Care
Seek evaluation from a PoTS knowledgeable clinician if you experience:
Frequent fainting
Persistent dizziness
Severe fatigue
Difficulty standing
Worsening brain fog
Symptoms that interfere with school work or daily activities
A PoTS specialist can determine whether your symptoms are related to PoTS, low blood pressure, another autonomic disorder, or a combination of conditions.
Get Expert Help
If you or a loved one is experiencing symptoms of PoTS or low blood pressure professional evaluation is essential.
For more information specialist support and expert care visit POTS.net.