Dysautonomia in ME/CFS, Long Covid and Fibromyalgia: What You Need to Know

If you live with ME/CFS, Long Covid or Fibromyalgia, you may have experienced symptoms such as dizziness, palpitations, fatigue, brain fog, digestive problems or feeling worse when standing. While these symptoms can seem unrelated, they may all have a common cause: dysautonomia.

Dysautonomia is increasingly recognised as an important contributor to illness severity in all three conditions. Understanding how it affects the body can help explain symptoms and guide practical management strategies.

What is Dysautonomia?

Dysautonomia refers to dysfunction of the autonomic nervous system (ANS), the part of the nervous system that automatically controls essential functions such as:

• Heart rate

• Blood pressure

• Digestion

• Breathing

• Body temperature

• Blood circulation

  
  

The ANS has two main branches:

The sympathetic nervous system ("fight or flight"), which prepares the body for action and stress.

The parasympathetic nervous system ("rest and digest"), which promotes recovery, relaxation and healing.

In healthy individuals, these systems work together to maintain balance. In dysautonomia, this balance is disrupted, often resulting in an overactive stress response and reduced ability to recover.

How Common is Dysautonomia?

Research suggests autonomic dysfunction is extremely common in ME/CFS, Long Covid and Fibromyalgia.

Recent studies have found that:

• Up to 97% of people with ME/CFS report at least one autonomic symptom (1).

• Around 70–80% of people with Long Covid experience significant autonomic symptoms (2)(3)(4)

• Fibromyalgia is strongly associated with autonomic nervous system dysfunction and orthostatic intolerance (5)(6)(7).

  
  

In all three conditions, dysautonomia is linked to greater fatigue, cognitive difficulties and reduced quality of life.

Common Symptoms of Dysautonomia

Because the autonomic nervous system affects so many body functions, symptoms can be wide-ranging.

Orthostatic Intolerance

One of the most common features of dysautonomia is orthostatic intolerance – symptoms that occur when sitting or standing upright.

These may include:

• Dizziness

• Light-headedness

• Feeling faint

• Palpitations

• Rapid heart rate

• Fatigue

• Brain fog

  
  

Many people notice their symptoms improve when they lie down.

Postural Orthostatic Tachycardia Syndrome (PoTS)

PoTS is a form of dysautonomia characterised by an excessive increase in heart rate on standing.

Symptoms may include:

• Palpitations

• Tachycardia (rapid heart rate)

• Dizziness

• Breathlessness

• Fatigue

• Exercise intolerance

  
  

Some people also develop a bluish or purple discolouration of the feet and lower legs due to blood pooling.

Cardiovascular Symptoms

Dysautonomia can affect circulation and blood pressure regulation, leading to:

• Palpitations

• Low blood pressure

• Irregular heartbeat

• Reduced blood flow to the brain

  
  

This reduced circulation may contribute to fatigue, brain fog and exercise intolerance.

Temperature Regulation Problems

Many people experience:

• Cold hands and feet

• Heat intolerance

• Excessive sweating

• Reduced sweating

• Difficulty regulating body temperature

  
  

Digestive Symptoms

Autonomic dysfunction can disrupt normal digestive processes, causing:

• Constipation

• Reflux

• Bloating

• Nausea

• Altered bowel habits

  
  

Other Symptoms

Additional symptoms may include:

• Dry eyes and dry mouth

• Frequent urination

• Light sensitivity

• Visual disturbances

• Cognitive dysfunction

  
  

How is Dysautonomia Diagnosed?

Diagnosis usually involves a combination of symptom assessment and testing.

Common investigations include:

• Blood tests to rule out other causes of symptoms

• Active stand testing

• Tilt table testing

• Heart rate variability assessment

  
  

Tilt table testing is considered the gold-standard test for diagnosing conditions such as PoTS and orthostatic hypotension.

Practical Strategies for Managing Dysautonomia

While there is no single cure, many people experience meaningful improvements through a combination of lifestyle, nutritional and medical approaches.

1. Stay Well Hydrated

Low blood volume is common in dysautonomia.

Many specialists recommend:

• Drinking around 2–3 litres of fluid daily

• Drinking water before getting out of bed in the morning

• Increasing fluid intake during hot weather

  
  

2. Optimise Salt and Electrolytes

For some people, increasing salt intake can help improve blood volume and circulation.

Electrolytes such as sodium, potassium and magnesium are important for:

• Blood pressure regulation

• Nerve signalling

• Muscle function

  
  

However, increased salt intake is not appropriate for everyone and should be discussed with a healthcare professional.

3. Stabilise Blood Sugar

Blood sugar fluctuations can worsen autonomic symptoms.

Helpful strategies include:

• Eating regular meals

• Including protein, healthy fats and fibre with meals

• Limiting sugary foods and refined carbohydrates

  
  

This may help reduce adrenaline surges, palpitations and energy crashes.

4. Prioritise Nutrient-Dense Foods

A diet rich in whole, minimally processed foods provides important nutrients that support nervous system function.

Particular attention should be paid to:

• Magnesium

• Vitamin D

• B vitamins

• Vitamin C

• Iron (if deficient)

5. Pace Your Activity

For people with ME/CFS and Long Covid, pacing remains one of the most effective management strategies.

Key principles include:

• Staying within your energy limits

• Avoiding "push-crash" cycles

• Breaking tasks into smaller steps

• Building regular rest periods into the day

  
  

6. Consider Compression Garments

Compression tights or abdominal compression garments can help reduce blood pooling in the legs and abdomen.

Many people find this improves dizziness, fatigue and upright tolerance.

7. Use Postural Strategies

Simple adjustments can help minimise symptoms:

• Stand up slowly

• Avoid standing still for long periods

• Sit down when symptoms begin

• Elevate your legs when resting

  
  

8. Practice Diaphragmatic Breathing

Slow, controlled breathing can help activate the parasympathetic nervous system and reduce autonomic overactivity.

Potential benefits include:

• Reduced palpitations

• Improved heart rate variability

• Better stress regulation

• Reduced breathlessness

  
  

9. Manage Heat Exposure

Heat can worsen symptoms by causing blood vessels to dilate.

Helpful strategies include:

• Staying cool in hot weather

• Drinking extra fluids

• Using fans or cooling aids

• Avoiding very hot baths and showers

  
  

10. Prioritise Sleep

Good sleep habits support autonomic regulation.

Try to:

• Keep regular sleep and wake times

• Limit caffeine later in the day

• Reduce screen exposure before bed

• Keep your bedroom cool, dark and quiet

  
  

Key Takeaway

Dysautonomia is a common but often under-recognised feature of ME/CFS, Long Covid and Fibromyalgia. It can affect multiple body systems and contribute significantly to fatigue, dizziness, cognitive problems and reduced daily functioning.

Although there is rarely a single solution, many people benefit from a combination of hydration, nutrition, pacing, circulatory support and nervous system regulation strategies.

The goal is not to push through symptoms, but to support the body's ability to maintain stability and improve resilience over time.