Can POTS Cause Rashes? What the Science Says

Rashes are one of the most frequently reported symptoms among people with postural orthostatic tachycardia syndrome (POTS), with one survey finding that roughly three out of four patients experienced them. Far from being a minor side note, skin changes in POTS range from blotchy red patches and hives to more unusual presentations like mottled, net-like discoloration on the legs. The connection between a heart-rate disorder and the skin surprises many patients and even some clinicians, but it makes more sense once you understand what POTS actually does to blood flow, the nervous system, and, in many cases, the immune system.

How Common Are Skin Problems in POTS

Studies consistently show that skin symptoms are not a rare oddity in POTS but a core part of the condition for most patients. In a survey of people diagnosed with POTS, rash was the single most commonly reported skin symptom, mentioned by 77% of respondents. The rashes tended to appear on the arms, legs, and trunk, and many patients described them as itchy or painful, with some noting they could spread over time.¹ A separate review of patients with orthostatic intolerance found that up to 85% had at least one skin-related symptom.²

Those numbers are strikingly high, and they raise an important point: if you have POTS and you are dealing with unexplained skin symptoms, you are in the majority, not an outlier. Yet skin problems in POTS often go unrecognized because most POTS care happens in cardiology or neurology clinics, where the focus is on heart rate and blood pressure rather than what is happening on the surface of the body.

The Range of Skin Changes People Experience

One reason skin symptoms in POTS can be confusing is that they do not all look the same. The range is wide, and different patients develop very different presentations. Reviews of dermatological findings in POTS describe manifestations spanning from livedo reticularis (a lacy, purplish mottling of the skin, usually on the legs) to Raynaud’s phenomenon (fingers or toes turning white or blue in response to cold or stress) to cutaneous flushing and erythromelalgia, a burning redness that typically affects the hands or feet.³

Beyond those, case reports and clinical series have documented a broader list of skin and related findings:

Raynaud’s phenomenon: reported by over half of POTS patients in one survey, involving episodic color changes in the fingers or toes triggered by cold or emotional stress.¹
Livedo reticularis: a net-like purple or blue discoloration of the skin, seen in about a quarter of patients in that same survey.
Flushing: sudden reddening of the skin, especially the face and chest, which can appear spontaneously or with triggers like standing up, heat, or stress.
Hives (urticaria): raised, itchy welts that come and go.
Erythromelalgia: episodes of burning pain with visible redness and warmth, usually in the hands or feet.
Nail and hair changes: including spoon-shaped nails, nail dystrophy, loss of eyebrow hair, and increased hair shedding (telogen effluvium).⁴

What ties these together is not the appearance of any single rash but the underlying problem: POTS disrupts the autonomic nervous system, and the autonomic nervous system controls blood flow through the skin, sweating, and the behavior of immune cells that live in the skin. When that control goes haywire, the skin shows it in a surprising number of ways.

Why a Heart-Rate Disorder Shows Up on the Skin

POTS is usually described as a problem with standing: your heart rate shoots up when you go from sitting or lying down to standing. But the underlying issue is broader than that. The autonomic nervous system, which manages heart rate, also regulates how blood vessels in the skin constrict and dilate, how sweat glands operate, and how the body responds to temperature changes. When autonomic regulation is impaired, the small blood vessels in the skin may not tighten properly when you stand. Blood pools in the legs, the vessels dilate excessively, and the result is visible redness, flushing, or that characteristic purple-red mottling.

Erythromelalgia, the burning redness of the hands and feet, appears to involve abnormal vasodilation in the extremities. Raynaud’s, where fingers go white or blue, involves the opposite: excessive vasoconstriction. That both extremes can occur in the same condition reflects how unstable vascular control becomes in POTS. The blood vessels overreact in one direction, then overcorrect in the other, depending on the moment. Livedo reticularis likely results from uneven blood flow through the small dermal vessels, creating that lace-like pattern on the legs.

Flushing episodes can be driven by sudden surges of adrenaline, which are common in the hyperadrenergic subtype of POTS. These surges cause blood vessels in the face and chest to open up abruptly, producing visible redness and warmth. Some patients notice that their rashes are clearly tied to position changes, heat exposure, or physical exertion, all of which stress the autonomic nervous system.

The Mast Cell Connection

Not all POTS-related skin problems are purely a matter of blood vessel misbehavior. A growing body of evidence points to mast cell activation as a significant contributor. Mast cells are immune cells that sit in tissues throughout the body, including the skin, and they release chemicals like histamine and prostaglandins when activated. When they overfire, the result can be flushing, hives, itching, and other skin reactions, along with gastrointestinal problems, headaches, and a general feeling of being unwell.

One study looked at 69 patients diagnosed with POTS and found that about two-thirds of them had additional symptoms beyond the typical heart-rate and blood-pressure complaints, including skin rashes, allergies, migraines, and gut problems. Among those patients, two-thirds showed at least one elevated lab marker suggesting mast cell activation, with raised prostaglandins and plasma histamine markers being the most common findings. Overall, roughly 42% of the POTS patients in the study had both the clinical symptoms and the lab evidence pointing toward a mast cell activation disorder.⁵

Earlier work specifically examined POTS patients who experienced flushing and found that those with elevated urine methylhistamine (a marker of histamine release) tended to have a hyperadrenergic pattern of POTS, with more intense surges of adrenaline on standing. The researchers cautioned that beta-blockers, a common first-line treatment for POTS, should be used carefully in these patients, and that treatment targeting mast cell mediators might be necessary instead.⁶

This matters practically. If your POTS-related skin symptoms are driven primarily by mast cell activation rather than simple blood-vessel instability, the treatment approach changes. Standard POTS interventions like increased salt, compression stockings, and exercise might help the heart-rate issues without touching the skin symptoms. In that case, antihistamines or other therapies aimed at mast cell mediators could make a real difference.

Hives as a Marker of Broader Symptom Burden

A recent study examined hives specifically among people with autonomic disorders, surveying 188 respondents. It found that roughly 43% reported experiencing hives sometimes, while about 18% said they had hives often or always. That means more than half of respondents had at least some experience with hives.⁷

What made the study particularly interesting is that hives did not simply track with the severity of the standing-up symptoms that define POTS. Instead, increasing frequency of hives was associated with a heavier overall autonomic symptom burden across several different body systems, including gastrointestinal symptoms, bladder problems, and vasomotor issues. Hives were also strongly associated with pain and tingling sensations. After the researchers controlled for other factors, hives remained independently linked to pain and tingling, suggesting that patients who get hives tend to be dealing with a more widespread pattern of nervous system dysfunction rather than just the circulatory problems.⁷

For patients, the takeaway is this: if you have POTS and frequent hives, it is worth having a broader conversation with your care team about your full range of symptoms. Hives in this context are not just an annoying add-on. They may signal that your autonomic dysfunction extends beyond heart rate and blood pressure, touching the immune and sensory systems too.

Sweating Problems and Heat Sensitivity

Skin changes in POTS extend beyond visible rashes into how the skin functions, especially when it comes to sweating and temperature regulation. In surveys of POTS patients, about 18% reported increased sweating and 4% reported decreased sweating. Among a group of 30 women evaluated more formally, over half had abnormal results on quantitative sudomotor axon reflex testing, a test that measures how well the small sweat-nerve fibers are working. The abnormalities tended to show up as patchy, reduced sweating, usually affecting the lower legs.²

In practice, sweating abnormalities can feed into the broader skin picture. Excessive sweating can cause heat rashes or prickly, irritated skin. Reduced sweating in some areas can lead to overheating and compensatory sweating elsewhere, creating an uneven and uncomfortable pattern. Many POTS patients describe being “heat intolerant,” feeling much worse in warm environments, with increased flushing, rashes, and worsened heart-rate symptoms. The sweating dysfunction helps explain why: if your body cannot cool itself properly, the autonomic stress worsens, and the skin bears the brunt.

When Ehlers-Danlos Syndrome and MCAS Overlap With POTS

Clinicians who treat POTS have long noticed that it frequently travels with other conditions, and two of the most common companions are Ehlers-Danlos syndrome (a connective tissue disorder that makes joints hypermobile and skin fragile) and mast cell activation syndrome (MCAS). These three conditions overlap so often in the same patients that they have been informally dubbed a “triad,” though the exact nature of the relationship remains debated.

A systematic review examining the prevalence of mast cell activation disorders and a related genetic trait called hereditary alpha tryptasemia among people with both POTS and Ehlers-Danlos syndrome found that while one study did reveal an association between MCAS, POTS, and EDS, the evidence overall was mixed. That one study came close to meeting full diagnostic criteria for MCAS in the overlap population, unlike most others in the review.⁸

The practical significance for skin symptoms is this: if you have POTS alongside hypermobile joints, stretchy or fragile skin, and frequent allergic-type reactions like hives and flushing, there may be more going on than POTS alone. Ehlers-Danlos syndrome can independently cause skin fragility, easy bruising, and poor wound healing, while MCAS can drive hives, flushing, and itching through excessive histamine release. Sorting out which condition is responsible for which skin symptom can be difficult, and in many patients, the answer is that multiple conditions are contributing simultaneously.

Managing Skin Symptoms in POTS

Treatment for POTS-related skin problems depends heavily on what is driving them. The standard POTS toolkit, which includes increased fluid and salt intake, compression garments, graded exercise programs, and sometimes medications like fludrocortisone or midodrine, addresses the underlying circulatory instability. When blood pooling and abnormal vessel behavior are the main culprits behind skin changes like livedo reticularis, dependent flushing, or erythromelalgia, these interventions can help by improving blood flow distribution.

In one published case, losartan, an angiotensin receptor blocker usually used for blood pressure, was reported to successfully treat dermatological manifestations of POTS, suggesting that targeting the vascular component directly can make a difference for some patients.⁴

For patients whose skin symptoms involve hives, itching, or flushing that seems allergic in nature, mast cell-targeted therapies become relevant. Clinicians have reported anecdotal improvement in POTS patients with mast cell activation symptoms when using antihistamines or other therapies aimed at mast cell mediators, though the evidence base is still limited.⁹ Common approaches include H1 antihistamines (like cetirizine or loratadine) combined with H2 antihistamines (like famotidine), which together block histamine at two different receptor types. Some patients also benefit from mast cell stabilizers like cromolyn sodium.

Beyond medications, practical steps can help. Avoiding known triggers, which for many POTS patients include heat, prolonged standing, alcohol, and certain foods, can reduce the frequency of skin flares. Cooling vests and strategic use of air conditioning help patients whose skin symptoms worsen with heat. Keeping a symptom diary that tracks skin flares alongside position changes, meals, and environmental conditions can help you and your clinician identify patterns and tailor treatment.

Why POTS Skin Symptoms Get Overlooked

Despite being reported by the majority of patients in studies, skin symptoms in POTS often fly under the radar in clinical practice. Part of the problem is the medical fragmentation that POTS patients face. A cardiologist is focused on your heart rate. A neurologist is focused on autonomic testing. A dermatologist, if you manage to get a referral, may not be familiar with POTS and may evaluate your rash in isolation, potentially attributing it to eczema, contact dermatitis, or an unrelated allergy. The result is that many patients bounce between specialties without anyone connecting the dots.

Another issue is that many POTS-related skin changes are transient. Flushing fades. Livedo reticularis comes and goes. Hives appear for an hour and vanish. If you are not actively symptomatic at the time of your appointment, there may be nothing visible for the clinician to examine. Photographing your skin changes when they occur and bringing the images to your appointment can be genuinely useful.

Research in this area is also still relatively thin. Most of the data comes from surveys, case reports, and small clinical series rather than large controlled studies. This means that while we can say with confidence that skin symptoms are common in POTS, the exact mechanisms, the optimal treatments, and the long-term trajectory of these symptoms are still being worked out. It is a space where patient reports have often run ahead of formal research, with online POTS communities documenting skin changes extensively for years before the medical literature caught up.

The Dependent Acrocyanosis Question

One of the most visually striking skin findings in POTS is something patients sometimes call “purple legs” or “red legs.” When standing, blood pools in the lower extremities due to poor vein constriction, and the legs take on a dusky red or purplish color that can look alarming. This is often described clinically as dependent acrocyanosis or dependent rubor. It is not technically a rash, since the skin surface itself is not erupting in bumps or welts, but it is a visible skin change that alarms patients and often prompts them to seek answers.

Dependent acrocyanosis in POTS resolves when you lie down and elevate your legs, which is a useful way to distinguish it from skin conditions that look similar but behave differently. It is driven by the same blood-pooling mechanism that causes the heart-rate spike on standing. Compression stockings that cover the legs and lower abdomen can reduce it, and some patients find that waist-high compression is more effective than knee-high stockings, since much of the pooling happens in the pelvic and thigh veins rather than just the calves.

If you notice your legs changing color when you stand and returning to normal when you lie down, it is worth mentioning to your clinician in the context of your POTS evaluation. On its own, dependent acrocyanosis is not dangerous, but it is a visible signal of how much blood your circulatory system is struggling to move against gravity, and it can help guide decisions about compression garment selection and medication dosing.