Myasthenia gravis
Overview
Myasthenia gravis is a rare long-term condition that causes muscle weakness.
Symptoms
Common symptoms of myasthenia gravis include: droopy eyelidsdouble visiondifficulty making facial expressionsproblems chewing anddifficulty swallowingslurred speechweak arms, legs or neckshortness of breathand occasionally serious breathing difficulties The symptoms tend to get worse when you're tired. Many people find they're worse towards the end of the day, and better the next morning after getting some sleep. Read more about thesymptoms of myasthenia gravis.
Causes
Myasthenia gravis is caused by a problem with the signals sent between the nerves and the muscles. It's an autoimmune condition, which means it's the result of the immune system (the body's natural defence against infection) mistakenly attacking a healthy part of the body. In myasthenia gravis, the immune system damages the communication system between the nerves and muscles, making the muscles weak and easily tired. It's not clear why this happens, but it's been linked to issues with the thymus gland (a gland in the chest that's part of the immune system). Many people with myasthenia gravis have a thymus gland that's larger than normal. Around 1 in 10 people have an abnormal growth of the thymus called a thymoma.
Treatment
Treatments to help keep the symptoms of myasthenia gravis under control include: avoiding anything that triggers the symptoms – some people find that things such as tiredness and stress make their symptoms worsemedicine to help improve muscle weaknesssurgery to remove the thymus gland (a small gland in the chest linked to myasthenia gravis) If the symptoms suddenly get worse – for example, you develop severe breathing or swallowing difficulties – you may need urgent treatment in hospital. Read more abouthow myasthenia gravis is treated.
When to see a doctor
See a GP if you have long-lasting or worrying symptoms that could be caused by myasthenia gravis. They'll ask about your symptoms and medical history. The GP may refer you to a specialist for tests to help diagnose myasthenia gravis or look for other possible causes of your symptoms. Tests you may have include ablood test, a test to see how well your nerves are working, and some scans, such as aCT scanorMRI scan. Read more abouttests for myasthenia gravis.