Myasthenia means muscle weakness

• Myasthenia affects all ages and genders. It is treatable and can be brought under good control with medication. In some circumstances, it can be fatal.
• It affects the muscles that let you move but not the automatic ones like your heart that you don't have to think about. Your brain tells your muscles to work, but the message doesn't get through.
• Myasthenia gravis, ocular myasthenia and Lambert-Eaton myasthenic syndrome are autoimmune conditions whereas congenital myasthenic syndrome is caused by an inherited genetic fault.