Myasthenia gravis (MG) is an autoimmune condition. When you have MG the antibodies that normally fight infections go wrong and end up attacking the communications system between your brain and your muscle movements. This results in muscle weakness, muscle fatigue and generally making you feel weak.

Symptoms

Often the first signs of myasthenia are with the eyes, these include droopy eyelids and possibly double vision. You may also find that you feel generally tired and have weakness in your neck arms and legs.

It is common that people find their faces are affected, this means smiling, making facial expressions or chewing may become difficult. If left untreated then this can evolve into difficulty swallowing and breathing, if this happens you should seek immediate medical attention.

In addition some peoples' speech can be difficult, especially if they have been talking for a long time, they may realise their speech has started to sound different, possibly slurred.

As the day goes on, some people find they are getting weaker and they may need a rest. Pushing yourself to do things like walk and talk, may make this even worse.

Diagnosis

To diagnose myasthenia gravis, a blood test is needed in order to detect that antibodies that are responsible for causing the condition. A test called electromyography (EMG) may be offered to you, in order to assess muscle activity.

Also a chest CT scan to assess the size and shape of the thymus gland. The thymus gland forms part of the immune system and problems with it, such as inflammation, are closely associated with myasthenia gravis.

Treatments

Every case of myasthenia is different so treatment that works very well for one patient may not have the same effect on another and vice versa.

Pyridostigmine (Mestinon)

Some people control their myasthenia with pyridostigmine alone, which temporarily improves nerve-muscle transmission to help muscle strength. The medication boosts the message from the nerve to the muscle resulting in easier muscle contraction and movement. It has to be taken periodically throughout the day for it to take full effect.

More information about pyridostigmine can be found on its designated information sheet.

Steroids and immunosuppressants

Prednisolone

This is a steroid that is often prescribed for myasthenia (typically on alternate days). Steroids reduced the production of antibodies by "damping down" the bodies immune system. Prednisolone is often started on a relatively high dose and gradually reduced until the optimum dosage is achieved. Symptoms usually start to improve 2-4 weeks after treatment is started. Maximum benefit is usually seen after 6-12 months of treatment.

More information can be found on its designated information sheet.

Azathioprine (Imuran®)

Azathioprine helps to reduce or suppress your body's own immune defense system. It acts slowly and can take up to a year to take full effect. Azathioprine can be used by itself or in conjunction with other medications. Regular blood tests are required.

More information can be found on its designated information sheet.

Methotrexate

Methotrexate helps to reduce or suppress your body's own immune defense system. It can take up to 8-12 weeks to take full effect. Methotrexate can be used by itself or in conjunction with other medications. Regular blood tests are required.

More information can be found on its designated information sheet.

Mycophenolate

Mycophenolate helps to reduce or suppress your body's own immune defense system. It can take up to 3-6 months to take full effect. Mycophenolate can be used by itself or in conjunction with other medications. Regular blood tests are required.

More information can be found on its designated information sheet.

Ciclosporin

Ciclosporin helps to reduce or suppress your body's own immune defense system. It can take up to 2-3 months to take full effect. Ciclosporin can be used by itself or in conjunction with other medications. Regular blood tests are required.

More information can be found on its designated information sheet.

Plasma exchange and IVIG

Plasma exchange and IVIG are two treatments that may offer rapid improvement (within a few days), for people who are particularly unwell. The treatments are similar and your specialist will decide which is the most appropriate. While the benefits only last a few weeks, it gives the time for other longer term treatments to become effective.

Plasma exchange

Plasma exchange is an emergency treatment to remove antibodies from your own blood. It is administered in hospital and the benefits generally last around 6 weeks.

IVIG (Intravenous Immunoglobulin)

This treatment takes place in hospital and involves being injected with normal antibodies from donated blood, it will temporarily change the way your immune system operates

Thymectomy

The thymus gland sits just behind the breastbone and, in childhood, it has a role in training the immune system. Sometimes it goes wrong and is implicated in MG. If the thymus gland is enlarged specialists often recommend its removal and some people go into remission following thymectomy, others experience a reduction in symptoms and manage with lower doses of medication but sadly for some there is no improvement at all.  It can take a couple of years for the benefits of thymectomy to be felt.

Occassionally, a thymoma (tumour of the thymus) is identified. In these cases a thymectomy is needed.

Nowadays, most thymectomies are performed by video-assisted thoracoscopic surgery (VATS), which is a quicker procedure with a shorter recovery period than the traditional sternotomy, which is still the preferred procedure for thymomas.