Myasthenia gravis is a chronic disease that is mainly due to dysfunctional transmission at the nerve-muscle junctions, which is easily remitted but prone to recurrence and is more likely in children and adolescents. Myasthenia gravis is characterized by the following symptoms. First of all, the patient is easily fatigued. In the morning, the muscle strength is good, but in the afternoon and evening, the muscles are more affected. If left untreated, other muscles may be involved, so that signals from the brain do not reach the muscles in time, and the muscles may lose their contraction function. In addition, if the patient speaks for a long time, the voice volume may become low or even indistinct, with a nasal sound. In severe cases, it may affect the chewing and swallowing of the mouth and teeth, and even make breathing difficult. The disease also causes stiffness of the facial muscles and a single facial expression, which prevents normal smiling and angry expressions. The eyelids may also droop, leading to double vision and strabismus of the eyes. Therefore, when suffering from myasthenia gravis, it is best to seek medical advice promptly. It is usually considered that this disease is easily diagnosed, so try to cooperate with your doctor. The vast majority of patients with good treatment do not affect their normal life.