Hyperadrenergic POTS: What the Evidence Actually Says, and What Actually Helps

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Adam Foster is the founder of The Fibro Guy and one of the leading voices in hypermobility, EDS, and chronic pain rehabilitation. A former Reconnaissance Soldier, he developed chronic pain after an IED blast in Afghanistan and built his approach from the ground up when the medical system had no answers. Since 2009 he has worked with thousands of people across eight countries, drawing on pain neuroscience, motor learning, and sensorimotor rehabilitation. He co-authored "No Pain, No Pain" with trauma psychologist Dr Mairi Harper, directed the documentary "Invisible Monster," and has been featured in Forbes, BBC Radio 4, ITV News, LiveScience, and The Telegraph.

A quick reminder of what POTS actually is

POTS is defined by what your heart rate does when you stand up. The diagnostic criteria are a sustained rise in heart rate of at least 30 beats per minute in adults, or at least 40 in adolescents, within ten minutes of standing, with symptoms of orthostatic intolerance that have been going on for at least three months, and crucially without a big drop in blood pressure to explain it ^[1]^[4]^[14]. That last part matters. If your blood pressure falls sharply when you stand, that is orthostatic hypotension, a different problem. In POTS the pressure holds, or even climbs, while the heart races to compensate for something.

The thing worth understanding early is that POTS is not one disease. It’s better thought of as a final common pathway, a single measurable end point that several different underlying problems can produce ^[5]. Calling someone’s diagnosis POTS is a bit like calling it a headache. Technically accurate, practically not very useful on its own though: it tells you what is happening without telling you why. Researchers describe it as heterogeneous and multifactorial for exactly this exact reason ^[5], and the 2019 National Institutes of Health consensus work leans into that same framing: distinct mechanisms, overlapping in real people, sitting under one label ^[1][24].

The subtypes usually described are neuropathic POTS, where a partial loss of the small nerve fibres in the legs lets blood pool so the heart races to compensate, hypovolaemic POTS, where the actual circulating blood volume is genuinely low, and the hyperadrenergic pattern, where the sympathetic nervous system is over-driven ^[5]^[6]^[7]. Most people are not one clean type. They have features of more than one, in different proportions, and those proportions can shift over time ^[5]. The researchers who have spent careers mapping the autonomic side of this are clear on the point: the subtypes overlap so heavily in real people that hyperadrenergic POTS is better understood as the pattern that dominates in someone than as a separate box you get sorted into ^[5]^[6]. We covered the full picture in our piece on the 2026 POTS guidelines, and this article zooms right in on the one that gets mislabelled the most.

What actually makes POTS hyperadrenergic

Noradrenaline, also called norepinephrine, is the main chemical messenger your sympathetic nervous system uses to raise your heart rate, tighten your blood vessels and get you ready to move. In the hyperadrenergic pattern, there is too much of it in circulation, particularly on standing. The working laboratory definition most clinicians use is a standing plasma noradrenaline level of 600 picograms per millilitre or higher, measured after a period upright ^[6]^[23]. Alongside that number, the tell-tale clinical sign is a blood pressure that rises when you stand rather than falls, driven by all that sympathetic outflow squeezing the blood vessels ^[6].

In practice it looks like a particular cluster of symptoms. Palpitations that feel dramatic rather than subtle. Tremor, often a visible shake in the hands that gets worse the longer you are upright. Surges that feel like adrenaline dumps, sometimes with flushing, sweating and a sense of dread that has no thought attached to it. A racing mind at night when your body should be settling. Cold, clammy hands. These are the features clinicians tend to associate with a high adrenergic state ^[6][9], and if you live with it, you will recognise the list immediately.

Here is the honest caveat though, and it is a big one, because the internet loves to hand out this label like a horoscope. The 600 picogram threshold is a useful marker, not a super clean dividing line. Noradrenaline levels are affected by hydration, medication, caffeine, stress, how long you were upright and how the blood was drawn, so a single number on a single day can mislead in both directions ^[5][6]. Plenty of people with genuinely adrenergic symptoms never get the test, and some who cross the threshold have strong features of the other subtypes too. The label describes a dominant pattern, it does not sort people into tidy boxes, and anyone who tells you otherwise is overselling the science ^[5][24].

Why the sympathetic system runs loud

This is where it gets genuinely interesting, and where the shallow articles stop. A high standing noradrenaline is the observation. It is not the cause. There are several different mechanisms that can drive it, they are not mutually exclusive, and understanding which ones are in play is what turns a label into something useful. Let’s go through them, warts and all, including the parts where the evidence is thinner than anyone selling a supplement would admit.

A faulty noradrenaline recycling system

The cleanest, best-documented mechanism comes from a single family studied back in 2000. When a nerve fires and releases noradrenaline, most of it is not broken down, it is hoovered back up by a protein called the noradrenaline transporter, or NET, and recycled. Shannon and colleagues described identical twins with orthostatic intolerance and racing heart rates who carried a loss-of-function mutation in the gene for that transporter, called A457P ^[8]. With the recycling pump broken, the noradrenaline that gets released hangs around in the synapse far longer than it should. The signal stays loud because the off switch is faulty, and the result was exactly the standing tachycardia and high plasma noradrenaline you would predict ^[8].

That exact genetic mutation is rare, and only a handful of families have ever been identified with it, so it does not explain most cases on its own. What made the finding so important is what it proved as a principle: that a problem with clearing noradrenaline, rather than making too much of it, can produce the whole hyperadrenergic picture ^[6]^[8]. Some researchers have raised the possibility that the transporter could also be turned down without a rare mutation, through changes in how the gene is switched on and off rather than a fault in the gene itself, which would in theory let the same mechanism reach far more people. It is worth being very clear about what that is. No study has actually shown it happening in those with POTS. It is an idea that fits what we know about how these systems can be dialled up or down, not a documented finding, so treat it as a line of thinking worth watching rather than a mechanism anyone can stand behind yet.

Central over-drive and a weak brake

In other people the problem is less about recycling and more about the volume being turned up centrally, from the brain and brainstem, with the natural braking system failing to rein it back in. Your baroreflex is that brake. It is a loop that senses blood pressure and adjusts heart rate and vessel tone to keep things stable. When that reflex is blunted, sympathetic outflow is not damped the way it should be, so standing produces an exaggerated adrenergic response and the heart rate overshoots ^[6]^[23]. This is one reason the hyperadrenergic pattern and the other subtypes blur together in real bodies: pooling in the legs from neuropathic changes can itself trigger a bigger compensatory sympathetic surge, so the mechanisms feed each other rather than sitting in separate lanes ^[5]^[6].

The autoimmune angle

A more recent and genuinely promising line of research is that some POTS is autoimmune. The idea is that the body produces antibodies that bind to the adrenergic receptors, the docking sites noradrenaline uses, and instead of blocking them they nudge them into activity. Li and colleagues found functional autoantibodies against alpha and beta adrenergic receptors in a group of people with POTS, and showed in the laboratory that these antibodies could alter receptor behaviour ^[10]. If your own immune system is quietly pressing on the accelerator, you would get a persistently high adrenergic state without any fault in the nerves or the transporter at all.

This is exciting, and it is also where honesty matters most. Finding an autoantibody in the blood is not the same as proving it causes the illness. Antibodies like these turn up in some healthy people too, the assays are not standardised across laboratories, and the field has not yet nailed down whether these antibodies drive POTS, worsen it, or are just travelling alongside it ^[11]^[24]. The link is strongest in the group whose POTS started after a viral infection, and the surge in cases after COVID has poured resources into exactly this question ^[11]^[22]. So it is a real and active area, not a solved one. Anyone offering you an autoimmune POTS diagnosis off a single antibody panel is a long way ahead of the evidence.

Mast cells and the flushing pattern

There is a specific subgroup where mast cells are part of the story, and it is one worth knowing about because it changes treatment. Mast cells are immune cells that release histamine and a raft of other vasoactive chemicals when they degranulate. Shibao and colleagues described people with hyperadrenergic POTS who also had mast cell activation, and the standout clinical feature in that group was flushing, alongside episodes of breathlessness, headache, lightheadedness and gut symptoms ^[9]. The proposed loop is that mast cell mediators can provoke sympathetic activation, and sympathetic activation can in turn trigger mast cells, so the two systems wind each other up ^[9].

The practical point from that work is a caution: in people whose hyperadrenergic symptoms come with prominent flushing, mast cell activation should be considered, because treatment may need to be directed at the mast cell mediators, and standard beta-blockers have to be used carefully in this group ^[9]. This overlap sits at the heart of the cluster we see so often in our clients, the tangle of POTS, mast cell issues and connective tissue problems that we pulled apart in our guide to the POTS, EDS and MCAS trifecta. If flushing is a big part of your picture, it is worth reading up on what mast cell activation syndrome actually is before you assume it is all adrenaline.

After a virus

A large number of people can date their POTS to a specific infection, and this has become impossible to ignore since 2020. Post-viral onset is common across the subtypes, and the autonomic dysfunction that follows a COVID infection frequently looks like POTS, hyperadrenergic features included ^[22]. The mechanisms proposed overlap with everything above, immune activation, small fibre changes, autoantibody production, so post-viral POTS is probably not a separate subtype so much as a common trigger that tips a susceptible nervous system into one of the patterns we have already described ^[11]^[22]. If your symptoms started or stepped up after an illness, that history is worth telling your clinician, because it shapes what is worth investigating.

The hypermobility and EDS connection

Almost every article on hyperadrenergic POTS leaves this part out, and it is the one that matters most to the people we work with. If you have hypermobile Ehlers Danlos syndrome or a hypermobility spectrum disorder, POTS is far more common in you than in the general population, and the two turn up together often enough that orthostatic symptoms in a hypermobile person should always prompt a proper look at the autonomic side ^[17]. Miller and colleagues applied the full 2017 hEDS criteria to 91 people with POTS and found that 31 percent, that is 28 of them, met the clinical criteria for hEDS, with a further 24 percent showing generalised joint hypermobility without meeting the full hEDS threshold ^[17]. That is a striking amount of connective tissue involvement in a POTS clinic, and hEDS is the most common of the Ehlers-Danlos subtypes to begin with ^[18].

Why the two travel together is not fully mapped, but the pieces make sense. Connective tissue that is more compliant means blood vessels that stretch a little more under pressure, which allows more blood to pool in the lower body on standing, which demands a bigger compensatory response from the heart and the sympathetic system ^[17]. On top of that, mast cell involvement is more common in hypermobile people, and we have just seen how tightly mast cells and the adrenergic system are linked ^[19]. So in a hypermobile body you can get vessel-level pooling, a jumpy immune contribution and an over-driven sympathetic response all in the same person, which is a fairly direct route to the hyperadrenergic picture. If you are still working out where your own symptoms fit, our explainer on how hypermobility and EDS are diagnosed is a sensible starting point, and the wider hypermobility and EDS guide pulls the whole system together.

The anxiety problem

Almost everyone with hyperadrenergic POTS has been told at some point that they are just anxious, and understanding why that happens, and why it is usually wrong, is genuinely important. Start with the obvious. A surge of noradrenaline produces a racing heart, a tremor, sweating, chest tightness and a flood of dread. That is, chemically, close to what your body does during a panic attack. So a person turns up describing exactly that, a doctor who has not measured a standing heart rate reaches for the familiar explanation, and the physiological event gets relabelled as a psychiatric one ^[20]. The symptoms overlap enough that it is an easy mistake to make in a short appointment.

The evidence gives us a more careful picture than either extreme allows. It is not that people with POTS never have anxiety, and it is not that POTS is secretly all in the mind. Reviews of the psychological research in POTS find that, as a group, people with POTS do not show the raised rates of true psychiatric anxiety disorders you would expect if anxiety were the driver, even though they report a lot of physical symptoms that anxiety questionnaires happen to score ^[20]. What does show up is something called anxiety sensitivity, a heightened attention to and worry about bodily sensations, which makes complete sense in someone whose body keeps generating alarming ones, plus real impacts on quality of life and cognition from living with the condition ^[21]. The mislabelling matters because those two things call for different responses. A physiological adrenergic surge needs the nervous system settling down, not reassurance that nothing is wrong.

This is the loop we spend a lot of time on with clients, and it is the useful bit. The adrenergic surge is physical. The fear that follows, once you have learned that these episodes are unpredictable and horrible, is a normal and understandable psychological reaction to a physical event, and the fear then feeds more arousal, which feeds the physical symptoms. It is a nervous system stuck in a high-arousal state with a very good reason to stay there. The way out is not to argue about whether it is physical or mental, because it is plainly both, but to work on turning the arousal down at the level of the body. We go much deeper into this in our piece on hypermobility and anxiety, which covers the same wiring from a different angle.

How it gets diagnosed

The foundation is the same as for any POTS. A clinician measures your heart rate and blood pressure lying down and then across ten minutes of standing, either as an active stand test or on a tilt table, and looks for that sustained heart rate rise without a matching blood pressure drop ^[1]^[2]. You do not need a specialist tilt table for the basic diagnosis, a careful active stand test in a normal consulting room can meet the criteria ^[2]. What points towards the hyperadrenergic pattern specifically is the blood pressure climbing rather than falling on standing, the symptom cluster of tremor, surges and palpitations, and where it is measured, a raised standing plasma noradrenaline ^[6]^[23].

The noradrenaline blood test is helpful but far from universal. It has to be done properly, with the sample taken supine after a rest and again after a set time standing, and it is not offered everywhere ^[6]. A normal result does not rule out adrenergic symptoms, and a high one on a bad day does not seal a subtype, for all the reasons we covered earlier. Treat the number as one piece of evidence sitting alongside your symptom pattern and your standing observations, not as a verdict ^[5]^[6]. One more honest note on the road to diagnosis: it is often slow. The large patient survey behind much of what we know found long delays and many wrong turns before people landed on the right label, so if it took you years and several dismissals, you are unfortunately in normal company ^[13].

What actually helps

Before we go through the options, the honest headline: the treatment evidence in POTS as a whole is thin, most trials are small, and the hyperadrenergic subtype specifically has less high-quality data than anyone would like. A 2026 systematic review of POTS treatment and a separate review of oral medications both land in the same place, some things show real promise in small studies, very little has the kind of large trial behind it that you would want, and a lot of prescribing is sensible extrapolation rather than proof ^[25]^[26]. None of that is a reason to do nothing, but it does mean expecting a period of trial and error, and being wary of anyone who promises certainty.

Foundations, with one important caveat

The usual non-drug foundations for POTS still apply: adequate fluids, sensible attention to blood volume, compression to reduce pooling, and avoiding the triggers that spike symptoms ^[1]^[2]. The one place the hyperadrenergic pattern differs is salt. Aggressive salt loading is a mainstay for the hypovolaemic pattern, where low blood volume is the actual problem, but in a strongly hyperadrenergic presentation, where blood pressure already rises on standing, piling in salt is less obviously helpful and needs a clinician’s judgement rather than a blanket rule ^[6]. We went into the detail of this in our article on POTS and salt, and compression is worth its own look in our piece on compression garments. The point is that one-size advice does not fit these subtypes, which is the whole reason getting the pattern right is useful.

Turning the arousal down

Our approach earns its place here, because a chronically over-driven sympathetic system is exactly the thing a good rehabilitation programme is built to influence. The physiological deconditioning that comes with months of feeling too rough to move makes POTS worse across the board, and structured exercise is one of the few interventions with decent supporting evidence, provided it starts in the right position ^[12]. That means beginning recumbent or semi-recumbent, on a rowing machine, a recumbent bike or in water, so you are not fighting gravity and orthostatic stress at the same time, then grading up slowly ^[12]. Thrown at it the wrong way, with upright cardio and too much intensity, exercise makes hyperadrenergic POTS worse, which is why so many people conclude that exercise is not for them when the real problem was the starting position. We laid the first step out in detail in POTS and exercise.

Alongside the graded loading, the arousal side needs direct work. Slow breathing that lengthens the exhale, done regularly rather than only mid-crisis, nudges the balance back towards the parasympathetic side and is a low-risk skill worth building. Pacing matters, because pushing into a crash spikes sympathetic drive for days afterwards. And a lot of people with POTS over-breathe on standing without realising it, dropping their carbon dioxide and worsening the lightheadedness, which is a specific and fixable habit we covered in our piece on breathlessness and carbon dioxide tolerance. None of this is a cure, and none of it replaces medical management where that is needed, but it targets the actual mechanism, an over-aroused nervous system, rather than just chasing the heart rate number.

Medication

Several drugs are used, and the ones aimed at the adrenergic pattern are worth understanding because the logic behind them is clean even where the trial data is modest. Low-dose beta-blockers are a common first choice, and there is a genuinely useful study here. Raj and colleagues compared propranolol against placebo, and low against higher doses, and found that a low dose of around 20 milligrams lowered standing heart rate and improved symptoms, with the standing heart rate an hour after dosing sitting at 90 beats per minute on low-dose propranolol against 110 on placebo ^[15]. The counterintuitive finding was that a higher 80 milligram dose lowered the heart rate more but did not improve symptoms better, and some symptoms only improved on the low dose, so the authors concluded that chasing full beta-blockade is a mistake ^[15]. Less is more, as the paper itself put it.

Ivabradine is the other option that has actually been tested in this specific group. It slows the heart rate through a different route from beta-blockers, acting directly on the sinus node without touching blood pressure, which makes it attractive when blood pressure is already on the high side. A small randomised, double-blind, placebo-controlled crossover trial of 22 people with hyperadrenergic POTS reported a significant reduction in heart rate and improvements in physical and social functioning, with a trend towards lower standing noradrenaline ^[16]. It is a small trial, and small trials need replicating before anyone gets carried away, but it is one of the few pieces of evidence aimed squarely at this subtype, and we covered the drug in full in our article on ivabradine for POTS.

Beyond those, clinicians sometimes use central sympatholytics such as clonidine or methyldopa, which act on the brain to reduce sympathetic outflow directly, a logical fit for a centrally driven adrenergic state, though the evidence base is smaller still and side effects like sedation limit their use ^[25]^[26]. The mast cell caveat from earlier belongs here too: in people whose hyperadrenergic symptoms come with prominent flushing, beta-blockers need real caution, and the mast cell side may need addressing before the adrenergic side settles ^[9]. All of this is a conversation for a clinician who knows autonomic medicine, ideally one who will treat the medication as part of a plan that also includes the graded loading and arousal work, not as the whole answer.

Frequently asked questions

Is hyperadrenergic POTS just anxiety?

No. The adrenaline surges, tremor and palpitations are a measurable physiological event driven by high sympathetic activity, not a psychiatric one, and as a group people with POTS do not show the raised rates of true anxiety disorders you would expect if anxiety were the cause ^[20]. What is real is that living with unpredictable adrenergic episodes understandably makes people more attentive to and worried about bodily sensations, and that worry can feed the arousal ^[21]. The symptoms are physical, the feelings about them are a normal response, and both deserve to be taken seriously rather than one being dismissed.

Do I need a noradrenaline blood test to know I have it?

Not necessarily. The standing plasma noradrenaline test, with a threshold around 600 picograms per millilitre, supports the diagnosis, but it has to be done correctly and is not available everywhere ^[6]. A blood pressure that rises rather than falls on standing, together with the classic symptom cluster, points to the pattern even without the number ^[6]^[23]. The test is one piece of the picture, not a pass or fail, and a single reading on a single day can mislead in either direction ^[5].

Does salt loading help hyperadrenergic POTS?

It is less clear-cut than for other subtypes. Salt and fluid loading is a mainstay for hypovolaemic POTS, where blood volume is genuinely low, but in a strongly hyperadrenergic presentation, where blood pressure already climbs on standing, aggressive salt loading is not automatically helpful and should be guided by a clinician rather than applied as a blanket rule ^[6]. This is exactly why sorting out which pattern dominates is worth the effort, and we go into the salt question in more detail here.

Is it linked to hypermobility and EDS?

Strongly. In a study applying the full hEDS criteria to 91 people with POTS, 31 percent met the criteria for hEDS and a further 24 percent had generalised joint hypermobility without the full diagnosis ^[17]. More compliant connective tissue allows more blood pooling on standing, and mast cell involvement, which is more common in hypermobile people, is closely tied to the adrenergic system, so the hyperadrenergic pattern turns up often in this group ^[17]^[19]. Orthostatic symptoms in a hypermobile person are always worth assessing properly.

Will it ever get better?

Many people do improve, though the honest answer is that the course varies and the high-quality long-term data is limited ^[3][24][25]. Graded exercise that starts in the right position has reasonable evidence behind it, arousal regulation targets the actual mechanism, and medication can take the edge off the heart rate while the rest of the work happens ^[12][15]. Progress is usually gradual rather than sudden, and expecting some trial and error is realistic rather than pessimistic. The aim is a nervous system that is easier to live in, not an overnight fix.

The honest read

Hyperadrenergic POTS is a real and measurable pattern, driven by a sympathetic nervous system that stays louder than it should, for reasons that range from a faulty noradrenaline recycling pump to a blunted baroreflex, an autoimmune contribution, mast cell involvement or a viral trigger, often more than one at once. It is not anxiety, though it feels like it and gets mistaken for it constantly, and that mistake costs people years. If you are hypermobile, it is more common in you than in almost anyone, and the connective tissue, the mast cells and the adrenergic system all feed into the same picture. The evidence on treatment is thinner than we would like, so expect a bit of trial and error, but the direction is clear: get the pattern identified, be cautious with the blanket advice built for other subtypes, work on turning the arousal down at the level of the body, and use medication thoughtfully rather than aggressively. Understanding what your nervous system is actually doing is the first step to stopping it running the show.

– Adam –

References

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