What is Orthostatic Hypotension?
Orthostatic Hypotension
Orthostatic hypotension is a drop in blood pressure when you stand up, often caused by a problem with the autonomic nervous system (1). It is defined as a drop in systolic blood pressure of at least 20 mmHg, or in diastolic blood pressure of at least 10 mmHg, within 3 minutes of standing. Systolic pressure, the top number, is the pressure in your arteries when your heart beats. Diastolic pressure, the bottom number, is the pressure between beats (2).
In orthostatic hypotension, the autonomic nervous system doesn’t adjust well enough when you change position to keep enough blood flowing to your head. This can cause dizziness, lightheadedness or fainting, also called syncope. It can come on suddenly or be long-lasting, and it may or may not come with other symptoms.
Orthostatic hypotension should always be evaluated by your physician, since it can be caused by medications, heart problems and other medical or neurological conditions. Call 911 if you have chest pain, severe shortness of breath, fainting with an injury, or sudden weakness, numbness or trouble speaking.
How Common Is Orthostatic Hypotension?
Orthostatic hypotension is common. It can affect anyone at any age, but it becomes more common with age. It is also common after childbirth, after long periods of bed rest, and in teenagers during growth spurts (3).
What Causes Orthostatic Hypotension?
Orthostatic hypotension happens when the body has trouble managing blood flow during changes in position. The cause is different from person to person, and many people have more than one contributing factor. Possible causes include dehydration, anemia, blood loss, medication side effects, and problems with the nervous system, heart or hormones. Sometimes it is an early sign of a neurological condition such as Parkinson’s disease or multiple system atrophy, which is one reason a thorough evaluation matters.
Many areas of the brain help control the autonomic nervous system, including the insular cortex, the medial prefrontal cortex, the amygdala, the hypothalamus and the brainstem (1). Your inner ear’s balance system also tells your brain where your head is in relation to the rest of your body.
That information travels to the brainstem, where it combines with information from the cortex about where you are in space, so the brainstem can signal your blood vessels to tighten and keep blood flowing to your brain (4). Problems in one or more of the systems involved in this process can lead to orthostatic hypotension.
What Are the Symptoms of Orthostatic Hypotension?
Symptoms vary from person to person. They may include:
Severe, long-lasting fatigue
Lightheadedness or dizziness when changing position
Fainting
Nausea
Headaches
“Brain fog,” or trouble thinking and focusing
Neck and shoulder muscle tension
Chest pain
A pounding or irregular heartbeat
Blurred vision
Pale skin or discolored hands and feet
Not everyone has every symptom, and other symptoms are possible (1).
What Happens in the Nervous System With Orthostatic Hypotension?
When you go from lying down to standing, gravity pulls blood toward your feet. Normally, the autonomic nervous system tightens blood vessels so blood keeps flowing back up to the brain. In orthostatic hypotension, these reflexes don’t work well, and blood flow to the brain drops (5).
The body usually tries to make up for a drop in blood pressure by speeding up the heart. In some people, the heart rate doesn’t rise enough to help. In others, it rises so fast that the heart has less time to fill between beats. Either way, blood flow to the brain can fall further. This can cause dizziness and fainting, and falls can lead to injuries, especially in older adults. Some people with orthostatic hypotension also have high blood pressure when lying down, and research suggests that ongoing strain on the sympathetic nervous system may affect organs such as the heart and kidneys over time (6).
When the brain doesn’t get enough blood flow, many symptoms can appear. Your brain uses a great deal of energy, and when its supply is disrupted, many brain functions can be affected. Simple thinking tasks can feel like huge challenges, and simple physical tasks can be exhausting. Managing emotions can become very difficult. Nearly everything your brain does depends on steady blood flow, so when that system struggles, almost everything can feel like a struggle (2).
The Inner Ear’s Role in Blood Pressure
Your inner ear does more than help you balance. Through a reflex called the vestibulosympathetic reflex, signals from your inner ear reach blood pressure control centers in the brainstem and help adjust blood pressure and heart rate when you change position. This reflex responds to head movement before blood pressure has a chance to fall, while the baroreceptor reflex, which senses blood pressure in the large arteries, takes a second or two to catch up. That head start matters when you stand up quickly (7).
To use inner ear signals well, the brain has to clean them up. The inner ear’s motion sensors, the semicircular canals, give an imperfect signal, and its gravity sensors, the otoliths, can’t tell the difference between tilting your head and moving in a straight line. The brainstem and cerebellum solve these problems with a process called velocity storage, which combines and smooths these signals to estimate how your head is really moving and which way is down (7).
A 2022 study in the Annals of Clinical and Translational Neurology looked at 53 people with vestibular syncope, meaning fainting triggered by vertigo (8). More than a third had repeated episodes, and about 13% had potentially life-threatening injuries from falls. Abnormal inner ear tests were common, including abnormal head impulse tests in 31%, and about 1 in 5 also had orthostatic hypotension. The researchers proposed that when velocity storage produces a false sense of motion, the brain may adjust blood pressure for a position change that never happened. The baroreceptor reflex can then overcorrect, slowing the heart and dropping blood pressure, which can lead to fainting (8, 9).
The overlap between orthostatic hypotension and inner ear problems in this study supports the idea that the inner ear, brainstem and cerebellum are part of the system that keeps blood flowing to your brain when you stand, and that problems in how the brain processes motion and gravity can contribute to drops in blood pressure. This is a core part of how we approach orthostatic hypotension.
That’s why we measure these systems so carefully. Videonystagmography (VNG) records eye movements that reflect how the brainstem and cerebellum are processing inner ear signals, including velocity storage. The video head impulse test (vHIT) measures how well each semicircular canal is working. CAPS computerized posturography shows how well your brain uses inner ear, visual and body-position information to stay upright.
How Is Orthostatic Hypotension Usually Treated?
There is no established cure for orthostatic hypotension. It is usually managed with lifestyle changes, diet and exercise (10, 11). Your provider may also review your medications, since some can cause or worsen it. Some people benefit from medications that help the body hold on to salt and increase blood volume, or that tighten blood vessels (12). These treatments can help many people manage their symptoms.
How the NeuroRescue Program Can Help
Our care is designed to work alongside your physician, cardiologist, neurologist and other providers, never in place of them. Please don’t change or stop any medication, including blood pressure medication, or make changes to salt or fluid intake, without talking with your medical provider.
One of the brain’s most important jobs is figuring out where you are in the world. It uses your inner ear to sense where your head is in relation to gravity and how it’s moving, your muscles and joints to sense where your body is and what it’s doing, and your eyes to sense where you are in relation to everything around you. Your brain combines all of this into a picture of where you are, so you can respond to the world around you.
Your brain organizes this information as a set of maps: a vestibular map from your inner ear, a body map from your muscles and joints, a visual map from your eyes, and others. These maps need to agree with each other about where you are.
In some people with orthostatic hypotension, these maps may not match. Your eyes, inner ear and body may be sending different messages about where your head is in relation to gravity. Your inner ear also helps your body adjust blood pressure when you change position (7). When you go from lying down to sitting or standing, mismatched signals may make it harder for your brain to adjust blood flow to your head. Eye movement exercises can activate brain and brainstem areas involved in autonomic control (13).
Our approach is to first work on improving how your visual, vestibular and body-position systems function on their own. Then we gradually train them together in different positions relative to gravity, with the goal of helping your nervous system respond more appropriately when you change position.
Depending on your needs and test results, your program may include specific eye exercises (14), vestibular therapy (15), electrical stimulation (16), light therapy, also called photobiomodulation (17), and exercises in a virtual reality environment (18). The therapies we recommend are always chosen based on your testing and exam findings.
How the NeuroRescue Program Works
Your NeuroRescue Program begins with your Discovery Day. We start with a detailed history of your condition and your life on a timeline. This helps us understand the factors that may have contributed to where you are now, and identify related conditions that may be making it harder to move forward.
We measure how your visual, vestibular and balance systems are working through computerized analysis of your eye movements, inner ear reflexes and balance under different conditions. Our testing includes videonystagmography and saccadometry to measure several types of eye movements, the video head impulse test to measure inner ear reflexes, and CAPS computerized posturography to assess your balance under different sensory conditions. We also use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and your perception of vertical in a virtual reality environment.
We combine this with a thorough physical and neurological exam of your sensory, motor, autonomic and cognitive systems, including a passive tilt table test to see how your heart rate and blood pressure respond when you’re tilted upright (19). We also review any relevant lab work, imaging and prior testing, and integrate it with our findings.
Together, this helps us understand which parts of your nervous system are working well, which are struggling, and how quickly they tire. We use that information to design your personal NeuroRescue Program, aimed at improving function in the systems that need support and helping them work together. Our testing also helps us decide when to push and when to let you rest.
Our goal is to help you feel steadier and more confident when you stand up and move through your day.
Your Next Step
Feeling like the room might go dark every time you stand up is unsettling, but you don’t have to keep living with that worry alone. To find out if the NeuroRescue Program is right for you, contact one of our patient care coordinators to schedule your Discovery Day.
It’s never too late to take the next step.
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