Myasthenia Gravis and Long COVID

Understanding the Autoimmune and Neuromuscular Connection

covidCAREgroup Education Series

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder that causes weakness in skeletal muscles - the muscles responsible for voluntary movement.

While MG is considered rare, interest in this condition has grown since the COVID-19 pandemic, as viral infections are known triggers for autoimmune disorders.

Let’s review what we know and what we don’t.

What Is Myasthenia Gravis?

Myasthenia gravis occurs when the immune system produces antibodies that interfere with communication between nerves and muscles.

Normally:

• Nerves release acetylcholine
• Acetylcholine binds to receptors on muscle cells
• Muscles contract

In MG:

• Antibodies block or destroy acetylcholine receptors
• Nerve signals cannot effectively activate muscle fibers
• Muscle weakness results

This weakness typically worsens with activity and improves with rest.

Common Symptoms

MG often begins with:

• Drooping eyelids (ptosis)
• Double vision
• Facial weakness
• Difficulty chewing or swallowing
• Slurred speech

As the condition progresses, it may affect:

• Arms and legs
• Neck muscles
• Respiratory muscles

Weakness tends to fluctuate and worsen throughout the day.

Is COVID-19 Linked to Myasthenia Gravis?

Viral infections are well-recognized triggers for autoimmune diseases — including MG.

Research has identified cases of:

• New-onset MG following COVID-19 infection

• MG exacerbations in previously diagnosed patients

• Respiratory complications due to overlapping muscle weakness and viral lung disease

Proposed mechanisms include:

• Immune dysregulation

• Molecular mimicry (viral proteins resembling self-proteins)

• Cytokine-mediated inflammation

• Thymic immune activation

However:

COVID-19 does not directly cause MG in most individuals.
It may act as a trigger in susceptible individuals.

Infections can unmask or trigger autoimmune conditions but they are not the sole cause.

Neuromuscular Junction in Health vs. Myasthenia Gravis

A normal neuromuscular junction (left) vs one affected by myasthenia gravis (right). In a healthy junction, nerves release the neurotransmitter acetylcholine, which binds to receptors on the muscle surface and allows the muscle to contract efficiently. In myasthenia gravis, autoimmune antibodies damage or block these acetylcholine receptors, reducing the signal between the nerve and muscle. As a result, fewer receptors are available to receive the signal, leading to impaired muscle activation and the muscle weakness characteristic of MG.

What About Mast Cell Activation (MCAS)?

COVID-19 is associated with mast cell activation and histamine release in some individuals. While MCAS contributes to inflammation and autonomic symptoms in Long COVID, it is not established as a direct cause of myasthenia gravis.

MG is primarily an antibody-mediated autoimmune disorder targeting neuromuscular junction receptors.

That said:

• Inflammation can worsen autoimmune instability

• Immune dysregulation can contribute to disease flares

• Viral immune activation may increase symptom severity

More research is needed to clarify these relationships.

Risk Factors for MG

MG is rare, affecting approximately 20 per 100,000 people.

It is more commonly diagnosed:

• In women under 40

• In men over 50

• In individuals with thymus gland abnormalities

• In those with a family history of autoimmune disease

Diagnosis

Evaluation typically includes:

• Neurological exam

• Acetylcholine receptor antibody blood test

• Repetitive nerve stimulation testing

• Pulmonary function tests

• Chest CT or MRI (to evaluate thymus gland)

The Edrophonium (Tensilon) test was historically used but is now less common.

Treatment Options

There is currently no cure for MG, but treatments help manage symptoms.

Medications

• Cholinesterase inhibitors (Pyridostigmine) – improve nerve-muscle signaling

• Corticosteroids (Prednisone, Methylprednisolone)

• Immunosuppressants

• Biologic therapies in advanced cases

Procedures

• Thymectomy

• Plasma exchange

• Intravenous immunoglobulin (IVIG)

Nutrition & Lifestyle Considerations

Because MG affects chewing and swallowing:

Helpful strategies include:

• Moistening solid foods

• Choosing soft proteins (fish, poultry)

• Avoiding dry, crumbly foods

• Eating smaller, more frequent meals

General immune-supportive habits remain important:

• Adequate hydration

• Sleep hygiene

• Stress management

• Exercise within tolerance

These do not cure MG — but they support overall resilience.

Potential Complications

Myasthenic Crisis - Life-threatening respiratory muscles weakness. Symptoms: Shortness of breath; Difficulty breathing; Inability to clear airway. Requires emergency care.

Thymoma - Tumor of the thymus gland (associated in some MG cases).

Thyroid Disorders - Both hypothyroidism and hyperthyroidism occur more frequently in MG patients.

Is MG Preventable?

MG is not preventable.

However, known triggers for exacerbations include:

• Emotional stress

• Infections

• Fever

• Overexertion

• Certain medications (muscle relaxants, some antibiotics)

• Extreme temperatures

Managing these triggers can reduce flare risk.

COVID-19 Considerations for MG Patients

Individuals with MG may face increased risk from COVID due to:

• Respiratory muscle weakness

• Immunosuppressive therapies

• Increased vulnerability during infections

Vaccination decisions should be discussed with a neurologist.

What Support Options Exist for Long COVID Patients?

Many individuals benefit from structured support navigating care, pacing, and recovery planning.

ProMedView offers:

✔ Chronic Illness Coaching & Advocacy
✔ Long COVID Recovery Coaching

These services focus on helping individuals regain stability, communicate with providers, and plan recovery.

Final Thoughts

Myasthenia gravis is a rare but serious autoimmune neuromuscular disorder.

COVID-19 may act as an immune trigger in susceptible individuals — but it is not a simple cause-and-effect relationship.

Understanding immune balance, infection risk, and neuromuscular symptoms is key.

As always, covidCAREgroup remains committed to connecting the dots between emerging science and lived experience — responsibly.

Scientific References

• NIH: Myasthenia gravis at the crossroad of COVID-19: focus on immunological and respiratory interplay

• National Institute of Neurological Disorders and Stroke (NINDS) – Myasthenia Gravis Fact Sheet

• Gilhus NE. Myasthenia Gravis. N Engl J Med.

• Case reports of new-onset MG following COVID-19 infection