How Do You Know If Your Autonomic Nervous System Is Dysregulated?

Author: Lisette Portes, MD, Board-Certified Family Medicine Physician

Published / Last Reviewed: November 3, 2026 / Medically reviewed by Lisette Portes, MD

Autonomic dysfunction symptoms include lightheadedness when standing, a racing heart, fatigue, brain fog, digestive upset, abnormal sweating, and bladder changes. Doctors confirm a problem with orthostatic vital signs, symptom questionnaires, and sometimes formal autonomic testing, not by symptoms alone. Common causes include POTS, orthostatic hypotension, and diabetic neuropathy. Learn how the autonomic nervous system works and how chronic disease management addresses underlying causes.

What Are the Most Common Autonomic Dysfunction Symptoms?

The most common autonomic dysfunction symptoms are lightheadedness or dizziness when standing, a racing or pounding heart, fatigue, digestive problems, abnormal sweating, and bladder changes. Because the autonomic nervous system controls many organs at once, symptoms often appear in clusters that seem unrelated. Cleveland Clinic groups dysautonomia symptoms by body system and also lists brain fog, headaches, exercise intolerance, temperature swings, and vision changes. Symptoms often worsen with heat, long periods of standing, large meals, dehydration, alcohol, or a recent illness. Many people notice they feel better lying down. Symptoms alone do not confirm a diagnosis. Thyroid disease, anemia, medication side effects, dehydration, heart rhythm problems, and anxiety can look very similar. That is why a careful history and physical exam come first. Common symptom groups include:

Orthostatic intolerance: lightheadedness, blurred vision, or near-fainting on standing
Heart: palpitations, a fast heart rate on standing, or exercise intolerance
Digestive: nausea, early fullness, vomiting, constipation, or diarrhea
Sweating and temperature: too much or too little sweating, or temperature swings
Bladder and sexual: frequency, urgency, leakage, or erectile dysfunction
Brain and energy: fatigue, brain fog, headaches, and poor sleep

Is Nervous System Dysregulation the Same as Dysautonomia?

No. Dysautonomia is a medical term for a disorder of the autonomic nervous system, usually supported by objective findings, while nervous system dysregulation is a wellness phrase that is not a formal diagnosis. In wellness writing, dysregulated often describes feeling stuck in stress mode: wired but tired, anxious, poorly rested, or easily overwhelmed. Those experiences are real. They can reflect a stress response that stays switched on, which may disturb sleep, digestion, and focus. Clinical dysautonomia is different. It refers to measurable problems with autonomic reflexes, such as a blood pressure drop on standing or nerve damage that affects sweating. Cleveland Clinic estimates that more than 70 million people worldwide have some form of dysautonomia. The two ideas overlap, because chronic stress changes autonomic tone, but a medical evaluation helps tell them apart. Our article on chronic stress and the autonomic nervous system explores the stress side.

What Conditions Cause Autonomic Dysfunction?

Autonomic dysfunction can be primary, meaning it arises on its own, or secondary, meaning another condition or exposure causes it. Cleveland Clinic lists familial and idiopathic dysautonomia as primary forms. Secondary causes include diabetes, Parkinson's disease, multiple system atrophy, amyloidosis, lupus, Sjogren's syndrome, vitamin B12 deficiency, and long COVID. Diabetes matters greatly in primary care, because high blood sugar over time can damage small autonomic nerves. Medications are another common and often reversible factor. The MSD Manual lists diuretics, nitrates, alpha-blockers, calcium channel blockers, other blood pressure drugs, and tricyclic antidepressants among causes of blood pressure drops on standing. It also lists dehydration and prolonged bed rest. The same source notes orthostatic hypotension occurs in about 15% to 20% of older adults. Finding the cause matters because treatment depends on it. Key conditions include:

Postural orthostatic tachycardia syndrome (POTS): an excessive heart rate rise on standing
Orthostatic hypotension: a sustained blood pressure drop on standing
Diabetic autonomic neuropathy, including cardiovascular autonomic neuropathy
Neurally mediated (vasovagal) syncope: reflex fainting
Neurodegenerative disorders such as Parkinson's disease and multiple system atrophy
Post-infectious dysautonomia, including after COVID-19

What Is POTS, and How Is It Different From Orthostatic Hypotension?

POTS is defined by an excessive heart rate rise on standing without a significant blood pressure drop, while orthostatic hypotension is defined by a blood pressure drop on standing. A 2011 consensus statement led by Roy Freeman and published in Autonomic Neuroscience defines orthostatic hypotension as a sustained fall in systolic blood pressure of at least 20 mm Hg, or diastolic blood pressure of at least 10 mm Hg, within 3 minutes of standing or head-up tilt. For POTS, a 2022 review by Raj, Fedorowski, and Sheldon in the Canadian Medical Association Journal lists a sustained heart rate increase of at least 30 beats per minute within 10 minutes of upright posture, or at least 40 beats per minute in people aged 12 to 19. Symptoms must last at least 3 months, with no other cause for the fast heart rate. That review estimates POTS prevalence at 0.1% to 1%, most often in adolescent girls and young women.

How Is Autonomic Function Tested?

Autonomic function is usually assessed step by step, starting with a history, physical exam, and blood pressure and heart rate measured lying down and then standing. This simple check, called orthostatic vital signs or an active stand test, can reveal POTS or orthostatic hypotension patterns during a regular office visit. Questionnaires such as COMPASS-31, developed at Mayo Clinic, score symptoms across 31 questions. Blood tests may look for diabetes, thyroid problems, anemia, B12 deficiency, or autoimmune causes, and an electrocardiogram checks heart rhythm. When results are unclear or symptoms are severe, specialized autonomic laboratories perform formal testing. MedlinePlus notes that these labs often ask patients to avoid caffeine for 8 hours and alcohol for 12 hours beforehand. Wearable heart rate variability data can add context, but HRV is not a diagnostic test on its own. Common autonomic tests include:

Orthostatic vital signs or a 10-minute active stand test
Deep breathing test: heart rate changes during one minute of slow, deep breaths
Valsalva maneuver: heart rate and blood pressure response to forced exhalation
Tilt table test: monitored upright tilt, often 30 to 90 minutes in total
QSART or thermoregulatory sweat test: function of the nerves that control sweating
COMPASS-31 questionnaire: symptom burden across six domains

What Should Clinicians Know About Assessing Autonomic Dysfunction?

Clinicians should anchor assessment in standardized orthostatic testing and validated symptom scales, then refer for formal cardiovagal, adrenergic, and sudomotor testing when needed. Raj and colleagues describe an active stand protocol: 5 to 10 minutes supine for fluid equilibration, then heart rate and blood pressure at 1, 3, 5, 8, and 10 minutes of standing. COMPASS-31, validated by Sletten and colleagues in Mayo Clinic Proceedings in 2012, scores orthostatic intolerance, vasomotor, secretomotor, gastrointestinal, bladder, and pupillomotor domains. In diabetes, the ADA Standards of Care recommend assessing symptoms and signs of autonomic neuropathy starting at diagnosis of type 2 diabetes and 5 years after diagnosis of type 1, then at least annually. The ADA notes that cardiovascular autonomic neuropathy is associated with mortality independent of other risk factors, and early disease may show only reduced HRV with deep breathing. In long COVID POTS, the NIH RECOVER-AUTONOMIC trial of 181 adults found ivabradine lowered heart rate without significantly improving symptoms.

How Can an Integrative, Physiology-Focused Doctor Help With Autonomic Dysfunction Symptoms?

An integrative, physiology-focused doctor can help by taking your symptoms seriously, checking for common and treatable causes, and explaining how your autonomic nervous system ties them together. Dr. Lisette Portes is a board-certified family medicine physician seeing patients in Miami, with telehealth for patients located in Florida, in English and Spanish. She uses an autonomic, physiology-focused perspective when evaluating patients. You can discuss dizziness, palpitations, digestive changes, sweating, fatigue, wearable HRV data, and conditions such as diabetes through chronic disease management. When specialized testing is needed, referral to an autonomic specialist may be part of the plan. See a doctor soon if symptoms are new, worsening, or limiting daily life. Call 911 for fainting with injury, chest pain, a new irregular heartbeat with faintness, or stroke signs. Contact the office or call 305-328-5079. This article is general education, not medical advice.

Frequently Asked Questions About Autonomic Dysfunction Symptoms

What does autonomic dysfunction feel like?

Many people describe feeling lightheaded, shaky, or foggy when they stand, along with a pounding or racing heart. Others notice tiredness that rest does not fix, bloating or nausea after meals, sweating that seems off, or trouble tolerating heat. Symptoms often ease when lying down. Because these feelings overlap with many other conditions, a medical evaluation is the best way to understand the cause.

Can anxiety cause autonomic dysfunction symptoms?

Anxiety activates the sympathetic nervous system, so it can cause a fast heart rate, sweating, shakiness, and stomach upset. That overlap makes anxiety and dysautonomia easy to confuse. However, conditions such as POTS have objective criteria based on heart rate and blood pressure when standing. A clinician can check these measurements and look for other causes before attributing symptoms to anxiety alone.

What triggers autonomic dysfunction symptoms to flare?

Common triggers include heat, hot showers, standing still for long periods, large or high-carbohydrate meals, dehydration, alcohol, poor sleep, menstrual cycle changes, and viral illnesses. Sudden standing after lying down can also bring on symptoms. Keeping a simple diary of symptoms, fluids, meals, sleep, and activity can help you and your clinician spot patterns and plan practical adjustments.

Is there a blood test for autonomic dysfunction?

No single blood test diagnoses autonomic dysfunction. Blood work is used to find causes or contributors, such as diabetes, thyroid disease, anemia, and vitamin B12 deficiency. Cleveland Clinic notes that antibody tests for autoimmune conditions and catecholamine levels may also be used in some cases. Diagnosis relies mainly on symptoms, orthostatic vital signs, and specialized autonomic tests when needed.

When should I see a doctor for dizziness when standing?

See a doctor if dizziness on standing is new, frequent, getting worse, or interferes with daily life, or if you have diabetes or take blood pressure medicines. Seek emergency care by calling 911 if you faint and are injured, faint during exercise, have chest pain or shortness of breath, feel a new irregular heartbeat, or notice stroke signs such as face drooping or slurred speech.

Does a low HRV mean I have dysautonomia?

No. A low heart rate variability reading on a wearable is not a diagnosis. HRV changes with age, sleep, alcohol, illness, stress, training load, and medications, and it varies between devices. It can be a useful trend to discuss with a clinician, especially alongside symptoms. Learn more in our guide to heart rate variability and what it can and cannot tell you.

Autonomic Dysfunction Symptoms: How Can You Tell If Your Nervous System Is Dysregulated?