Muscle weakness can manifest as unexpected difficulty with regular muscle movements, such as climbing stairs, lifting an object, moving the eyes, or smiling, depending on the muscles that are affected. A person also may feel they get tired faster than usual when performing these activities.
For most people, early signs and symptoms of myasthenia gravis involve the muscles of the eyes and eyelids, including problems with eye movement, droopy eyes, or double vision. Symptoms affecting the face, neck, and throat are among the earliest symptoms for about 15% of patients, and may include changes in facial expressions and difficulties chewing, swallowing, or speaking.
How quickly a person’s myasthenia gravis progresses depends on a number of factors, but symptoms usually reach their peak severity a few years following disease onset. For the majority of patients with early eye-related symptoms who go on to develop a more generalized form of the disease, that transition usually happens in the first few years after eye symptoms are first noted.
Myasthenia gravis symptoms typically get worse during periods of activity and get better with rest. Certain disease triggers, such as stress, infection, hormonal changes, and some medications also may worsen symptoms. In general, MG symptoms do progress over the long term, typically reaching their worst about three years after disease onset.