Can You Recover from Orthostatic Intolerance?

Feb 08, 2024
orthostatic intolerance vest

This question — can you recover from orthostatic intolerance — has been partially inspired by a presentation by Dr. Peter Rowe, Prof. of Pediatrics at Johns Hopkins University. I was excited to learn from him the most important findings about orthostatic intolerance. OI, as it is often called, refers to the intolerance of being in an upright position including sitting and standing. As many as 50% of people with ME/CFS suffer from OI. OI is worth identifying if present because it is treatable. I have OI, and the treatment continues to make a huge difference in my ability to function day to day.

Dr. Rowe’s was one of many webinars I recently listened to. A webinar series made publicly available by the National Institutes of Health called the NIH ME/CFS Research Roadmap captured my attention for over 24 hours! I listened to webinar after webinar.

Each of the eight webinars included presentations by six to eight renowned researchers from prominent institutions on the topics of neurology, immunology, metabolism, genetics and genomics, chronic infection, physiology, circulation, and lesser-studied comorbidities as related to myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS).

I’ll be sharing information from these presentations over the coming months in Live! with Dr. Stein, my new subscription-based membership. This blog is a sneak peek of some of the information that could help you improve your health. So, let’s get back to the topic and the question — can you recover from orthostatic intolerance? First, let’s look at the red flags of OI.


What Are the Red Flags for Orthostatic Intolerance?

When I say “red flags” for orthostatic intolerance, I mean symptoms that alert you or your health-care team that there is something wrong. These red flags would include:

  • fainting,
  • having difficulty waiting in line without fidgeting or feeling unwell,
  • feeling worse in the heat or after a hot shower, and
  • preferring to read work or study in a reclined position or curled up in a fetal position.

About half of people with myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS) are reported to have OI, and this may be an underestimate because many physicians aren’t familiar with the condition. Many incorrectly believe that very low blood pressure is a sign of good health. OI is also associated with    

  • hypermobility of the joints causes higher-than-average flexibility and injury;
  • Ehlers-Danlos syndrome, a connective tissue disorder causing joint instability and lax blood vessels leading to blood pooling and low blood pressure;
  • mast cell activation syndrome, a condition in which all kinds of symptoms flare in response to food, medications, chemicals, heat, stress and other exposures; and
  • cervical and vascular compression syndromes in which the blood and nervous flow to and from the brain is impaired.

 When people with OI stand up, the blood pools to the lower limbs and there isn’t enough blood supply to the brain. This results in immediate symptoms when people sit or stand up, including:

  • lightheadedness
  • difficulties thinking and concentrating
  • headache
  • blurred vision
  • fatigue
  • exercise intolerance

 Additional symptoms are due to the body’s attempts to increase blood flow to the brain and heart. It does this by increasing adrenaline. These symptoms include:

  • shortness of breath
  • chest discomfort
  • palpitations
  • sweating
  • shakiness
  • nausea
  • anxiety

How Do You Test for Orthostatic Intolerance?

One way to test for orthostatic intolerance in the office is with the NASA lean test. In this test as shown to the left (from the Bateman Horne Centre), a person stands leaning back against a wall for 10+ minutes while blood pressure and heart rate are measured. Abnormal findings include a decrease in blood pressure, increase in heart rate, or a collapse of pulse pressure (the difference between the larger and smaller blood pressure numbers).

As helpful as the NASA lean test is, research by van Campen and colleagues in the Netherlands shows that 90% of people with myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS) have a decreased blood flow to the brain even if they have a normal heart rate and blood pressure. Van Campen et al. discovered this by using transcranial doppler ultrasound during a tilt table test. The doppler measures the blood flow directly in the four main arteries supplying the brain.



The image above is from a presentation by Dr. Rowe who was a co-investigator on the Dutch study. You can see in the image the dramatic drop in blood flow to the brain (the peaks of yellow are much less) when the research participant moves from lying down to standing up.


How to Improve Orthostatic Intolerance?

If you see yourself in this description of OI, what can you do about it? That is the good news. Many effective treatments can significantly improve your quality of life.

Step 1: Self-Management

  • Compression garments such as support hose and even lower body inflation suits help people with orthostatic intolerance feel and function better even if they don’t have obvious signs of leg swelling
  • Cooling garments — since heat expands blood vessels and worsens OI, staying cool can help. Strategies like wearing a hat in the sun, using ice packs, and wearing cooling vests (shown in the image) are worth trying if you get symptoms due to heat exposure.

  • Oral rehydration can make a big difference. Ensure you drink at least 2 liters/day with added salts . Since I first wrote about this in my August 2020 blog, new rehydration products have come on the market. Products like Trioral®, Ceralyte 90®, and Liquid IV® meet the WHO guidelines for oral rehydration.
  • Exercise — even though people with orthostatic intolerance often experience fatigue and post-exertional malaise, total inactivity worsens OI and can lead to a downward cycle of increasing symptoms. This is because the leg muscles play a significant role in moving blood up to the heart and the brain; if they become deconditioned, pooling in the legs increases. It’s recommended to start with recumbent (horizontal) exercise like mat pilates, a rowing machine, or a recumbent bike and slowly increase at your own pace, avoiding predetermined graded exercise programs.

Step 2: Medications

  • Drugs to constrict blood vessels — the most common and effective drug that constricts blood vessels to decrease the blood pooling in the lower body is midodrine.
  • Drugs to increase blood volume (fluid expanders) — fludrocortisone (Florinef®) causes the kidneys to retain salt and water in the body, thereby increasing blood volume. I have been on this medication for over 25 years, and it continues to be a game changer for me. Without it, I get dizzy, pass out frequently, have low energy, and can’t think clearly.
  • Drugs to control heart rate — when the blood pools in the lower body, there is less blood available for the heart to pump. In response, adrenaline increases, and the heart begins to beat faster and less efficiently. Beta blockers like atenolol are often effective to keep the heart rate from getting too high. The problem with beta blockers is that they also decrease blood pressure and can worsen fatigue. A newer drug, ivabradine is a possibility for people who don’t tolerate betablockers.
  • Drugs that increase acetylcholine – pyridostigmine blocks the degradation of acetylcholine. Acetylcholine is the primary neurotransmitter of the parasympathetic (rest and digest) nervous system. A study by Satish Raj and colleagues reported pyridostigmine decreased heart rate and improved quality of life and mood in people with orthostatic intolerance accompanied by high heart rate. Other studies since then have confirmed this result.

Since drugs are only available with a prescription, you will need to discuss your symptoms with your physician to access treatment. If your MD or NP is not knowledgeable about orthostatic intolerance, you may want to refer them to a Canadian review of postural orthostatic tachycardia syndrome (one type of OI) published in 2022. It lists the drugs and drug doses supported by research.

Myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS) is a complicated multi-system disease with few effective treatment options. For those who have symptoms of orthostatic intolerance as part of their symptom profile, treatment can make a big difference to activity capacity and quality of life.


So, Can You Recover from Orthostatic Intolerance?

It has generally been thought that orthostatic intolerance is a result of weak and dysfunctional connective tissue causing the arteries and veins to fill with blood instead of pumping it back to the heart. This decreased blood return to the heart and decreased flow to the brain causes most of the symptoms described in this blog. The causes of this dysfunction have been thought to be genetic variants that make connective tissue weaker, even though the genes at play can’t always be identified. To the extent that OI is caused by genetics, then full recovery is very unlikely as we can’t change our genes.

More recent research, however, suggests that some of the connective tissue weakness could be acquired — caused by health conditions such as mast cell activation. Mast cells release immune molecules and enzymes (proteases) that can weaken connective tissue. If this turns out to be a significant cause of orthostatic intolerance, the prognosis is better. There are treatments for mast cell activation syndrome (MCAS). If the release of the harmful chemicals can be decreased, it may be possible over time for the connective tissue to recover. This is a more hopeful spin on this very disabling clinical syndrome.

In the meantime, while we wait for research to provide more answers, the treatments outlined in this blog can help most people with orthostatic intolerance feel much better.


For more information you may want to refer to:

You can also join my live online sessions called Live! with Dr. Stein.  Held every two weeks, these sessions provide some new information and then I open up the session to questions from the attendees. I will also be featuring many guest experts on a variety of topics related to your health.



Van Campen, C., Verheugt, F. W. A., Rowe, P. C., & Visser, F. C. (2020). Cerebral blood flow is reduced in ME/CFS during head-up tilt testing even in the absence of hypotension or tachycardia: A quantitative, controlled study using Doppler echography. Clinical Neurophysiology Practice, 5, 50-58.

Video presentation by Dr. Peter Rowe to the Metro DC EDS and HSD Support Group July 9, 2023

Stein, E. (2020, Sep. 2). Summary of IACFS/ME Online Conference August 21, 2020. [Web log.]

Raj, S. R., Black, B. K., Biaggioni, I., Harris, P. A., & Robertson, D. (2005). Acetylcholinesterase inhibition improves tachycardia in postural tachycardia syndrome. Circulation, 111(21), 2734–2740.

Raj, S. R., Fedorowski, A., & Sheldon, R. S. (2022). Diagnosis and management of postural orthostatic tachycardia syndrome. Canadian Medical Association Journal, 194(10), E378.