Myasthenia gravis
Myasthenia gravis
Myasthenia gravis is a long term (chronic) illness that causes muscle weakness and tiredness.
It's a rare condition that usually affects the muscles that control:
- the eyes and eyelids
- the face
- speaking
- chewing
- swallowing
It can also affect muscles in other parts of the body.
It can affect people at any age, but it is seen most often in women under 40 and men over 60.
There are other, rarer types of myasthenia, which you can read about on myaware.
If you drive, you must tell the DVLA that you have myasthenia gravis.
Think about your safety
Try to avoid activities that could turn dangerous if sudden weakness comes on, such as swimming alone.
Common Symptoms
Symptom information is not available for this condition yet.
Emergency Warning Signs
Call 999 or go to A&E straight away if you have severe trouble breathing or severe trouble swallowing. You may need emergency hospital treatment.
⚠️ This symptom list is for educational purposes. Having these symptoms does not mean you have this condition. See a doctor for proper diagnosis.
Medicines Commonly Used
⚠️ These medicines are commonly used for confirmed diagnoses of this condition. This is NOT a recommendation or prescription. Treatment must be determined by your doctor.
No medicines have been linked to this condition yet.
When to See a Doctor
Call 999 or go to A&E straight away if you have severe trouble breathing or severe trouble swallowing. You may need emergency hospital treatment.
Diagnosis
Difficult to diagnose myasthenia gravis. Your doctor will ask about your medical history and symptoms.
You might need several tests to rule out other causes of your symptoms before you can be diagnosed.
Blood test
A blood test will look for a high level of antibodies (made by your immune system) which might be causing myasthenia gravis.
You might be offered another blood test at a later date if your first blood test is normal but you continue to experience worsening symptoms.
Electromyography
You might have electromyography (an EMG) to test your nerves and muscles.
During electromyography, you'll have small needles inserted into your muscles. This is to measure their electric activity. These are usually inserted around your eyes, forehead or arms.
The test will measure the signals from the nerves to the muscles. If the test detects a disruption in the signals, this might be a sign of myasthenia gravis.
Scans
You might have a computerised tomography (CT) scan. This is to check if the thymus gland in your chest is bigger than expected or has grown abnormally (a thymoma).
The thymus gland is part of your immune system. Problems with the thymus gland like inflammation (swelling), can be linked to myasthenia gravis.
A magnetic resonance imaging (MRI) scan might be used to check if your symptoms are being caused by an issue in your brain.
Treatment
Treatment for myasthenia gravis
There are treatments available that can help reduce the affects of your symptoms.
Medicine
You might be offered medicine to help treat myasthenia gravis. This could be:
- pyridostigmine – works by temporarily improving the nerve to muscle transmission to help muscle strength
- steroids – to reduce the activity of your immune system to stop it attacking the communication between your nerves and muscles
- other immunosuppressants – to reduce the activity of your immune system
Surgery
Your healthcare team might recommend surgery to remove the thymus gland (thymectomy).
After surgery symptoms should improve within the first few months. Symptoms can continue to improve for up to 2 years.
Surgery can reduce:
- the dose of steroids
- the need to take other immunosuppressants
- the chances of needing to go to hospital because of worsening symptoms
Surgery might not help myasthenia symptoms if you have a thymoma. Your healthcare team might still recommend having your thymus gland removed. This is because it can cause problems if it keeps growing.
Your thymectomy will usually be carried out through keyhole surgery. The thymus is removed using surgical instruments inserted through small cuts (incisions) in the chest.
Plasma exchange and IVIG
Plasma exchange and IVIG (intravenous immunoglobulin) can offer a quick improvement (within a few days) if you’re:
- very unwell
- having a myasthenic crisis
Plasma exchange is an emergency treatment that removes antibodies from your own blood. This treatment is given in hospital. The benefits can last around 6 weeks.
IVIG treatment involves an injection of normal antibodies from donated blood. This temporarily changes the way your immune system works.
Both treatments are similar and your healthcare team will decide which is the best option for you. Although the benefits only last a few weeks, it can give time for the longer term treatments to take effect and help improve symptoms.
Myasthenia gravis and pregnancy
You might find that, during pregnancy or after having a baby, your myasthenia gravis worsens. If you’re planning a pregnancy or become pregnant, you should speak to your healthcare team. Don’t stop taking your medications without first speaking to your healthcare professional.
Don’t include personal information e.g. name, location or any personal health conditions.
Prevention
Myasthenia gravis symptoms often flare up in response to certain triggers, so it helps to notice your own pattern and steer clear of what sets things off as much as you reasonably can.
Common triggers include:
- stress
- tiredness (fatigue)
- infections
- certain medicines
- surgery