Myasthenia Gravis: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Myasthenia Gravis?
A neurologist, a doctor who treats diseases of the brain, nerves and muscles, usually leads care for myasthenia gravis. Treatment can include medicines and sometimes surgery to remove the thymus gland. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is myasthenia gravis?
Myasthenia gravis, often called MG, is a chronic (long-lasting) disease that causes weakness in your voluntary muscles, the ones you can control.
The weakness gets worse with activity and better with rest. MG is an autoimmune disease. In an autoimmune disease, the immune system attacks healthy cells by mistake.
Symptoms
The symptoms depend on which muscles are affected. Common symptoms include:
- Weakness of the eye muscles.
- Drooping of one or both eyelids.
- Blurred or double vision.
- Changes in facial expressions.
- Speech problems.
- Weakness in the arms, hands, fingers, legs and neck.
- Trouble swallowing.
- Shortness of breath.
Trouble swallowing and trouble breathing need emergency care, as explained in the "When to see a doctor" section.
Double vision and drooping eyelids are the most common first symptoms.
Weakness differs from person to person. It can change from day to day.
Some people get severe weakness in the muscles that control breathing. This is called a myasthenic crisis, and it is a life-threatening emergency.
Causes and who gets it
MG is caused by an error in how nerve signals reach the muscles. The signals get blocked where nerve meets muscle.
In MG, the immune system makes antibodies, which are immune proteins, that block acetylcholine, a chemical messenger, from reaching the muscle. This makes the muscles weaker.
In many adults with MG, the thymus, a gland in the immune system, stays large. Some people develop thymomas, which are tumors of the thymus. Thymomas are most often harmless, but they can turn into cancer.
MG most commonly affects young adult women (under 40) and older men (over 60). It can happen at any age, including childhood.
MG is not contagious. It is usually not inherited, which means passed down in families. Occasionally, more than one person in the same family has it.
A myasthenic crisis may be triggered by infection, stress, surgery, or an adverse reaction to a medicine. Ask your doctor how any medicine might affect MG.
How doctors diagnose it
MG can be hard to diagnose. Many other problems cause muscle weakness.
The doctor asks about your history and symptoms and does a physical exam, including a neurological exam. In a nerve exam, the doctor checks muscle strength, coordination, sense of touch and eye movements.
Tests may include:
- A blood test for antibodies against the acetylcholine receptor or MuSK.
- Single fiber electromyography (EMG), a test of nerve and muscle signals. It is the most sensitive test.
- A CT or MRI scan of the chest to look for a tumor.
Treatment
There is no cure for MG, but treatments can improve muscle weakness and help with symptoms.
Treatments include:
- Anticholinesterase medicines, such as pyridostigmine, which slow the breakdown of acetylcholine and increase muscle strength.
- Immune-lowering medicines, called immunosuppressive medicines, can improve muscle strength. They can cause significant side effects and must be carefully monitored by a doctor.
- Monoclonal antibodies, which can also help lower the immune system's response. Other medicines target specific immune cells or the immune response.
- Eculizumab, a medicine the FDA has approved for adults with generalized MG who test positive for the acetylcholine receptor antibody.
- Plasmapheresis (plasma exchange) and intravenous immunoglobulin, which remove harmful antibodies in severe cases.
- Thymectomy, surgery to remove the thymus gland. It can reduce symptoms, possibly by rebalancing the immune system.
Other steps can help too. Regular gentle exercise may help some people. Avoiding stress and heat may also help.
If MG goes into remission, the person can usually stop taking medicines after talking with their doctor. Follow your doctor's instructions.
When to see a doctor
Call your doctor if you develop symptoms of myasthenia gravis.
Call 911 or go to the emergency room if you have trouble breathing or trouble swallowing. A myasthenic crisis is when the breathing muscles get too weak. It needs emergency care right away.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. A direct primary care doctor can review your medicines, work with a neurologist, and follow up between specialist visits.
Common questions
Is myasthenia gravis curable?
No. There is no known cure for myasthenia gravis. Treatments can help reduce and improve muscle weakness. Some people go into remission, which means no symptoms. It is usually temporary, but sometimes it can be permanent.
Is myasthenia gravis contagious?
No. MG is not contagious. It is usually not inherited. Sometimes more than one person in a family has it.
How long can someone live with myasthenia gravis?
Most people with MG live to an average life expectancy.
What is a myasthenic crisis?
A myasthenic crisis is when the breathing muscles get so weak that a person may need a ventilator, a machine that helps with breathing. It needs immediate emergency medical care, so call 911.
Sources
- NINDS - Myasthenia Gravis
- MedlinePlus - Myasthenia Gravis
- MedlinePlus - Myasthenia Gravis (Medical Encyclopedia)
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
