1, the mode of onset: a few rapid onset, most of the onset of insidious. 2, muscle weakness characteristics: (1) morning light and evening heavy; (2) fatigue phenomenon: skeletal muscle after a little activity will feel fatigue, and then see improvement after rest. The distribution of myasthenia gravis: (1) All transverse muscles in the body can be involved, and the distribution of affected muscles varies from person to person and from time to time; (2) More than 93% of patients have eyelid ptosis as the first symptom, and almost 100% of children with myasthenia gravis are mainly involved in the eye muscles. (3) The extraocular muscles are most likely to be involved and are often the only symptom in the early stages. (4) Other patients can involve the muscles of mastication, throat muscles, chewing weakness, reduced voice, nasal voice or hoarseness, swallowing difficulties; (5) Involvement of the muscles of the whole body, generalized weakness; (6) Involvement of the respiratory muscles, respiratory effort or difficulty.4 Muscle atrophy is generally absent in patients with advanced generalized type, there may be atrophy of the scapular girdle muscle, biceps, deltoid and quadriceps muscles, etc. 4, relapse or aggravation of the triggering factors: (1) mental trauma such as excessive sadness, anger, various infections of the body such as colds, acute upper respiratory tract infections, overexertion, endocrine disorders, immune dysfunction, women’s menstruation, pregnancy or childbirth, and many other factors may trigger the relapse or aggravation of myasthenia gravis. (2) Some antibiotics, such as mucomycin, streptomycin, kanamycin, sleeping pills, etc. have the effect of aggravating myasthenia gravis and should be noted. 5, prognosis: myasthenia gravis has a chronic and prolonged course, alternating between remission and deterioration, and recurrence has become a characteristic of the disease. If the aforementioned causes are clearly recognized, and corresponding preventive and active treatment measures are taken, the recurrence and deterioration of the disease can be avoided to a large extent. 6, precautions: If the infection or improper medication causes generalized muscle weakness, swallowing difficulty, choking cough or with chest tightness, shortness of breath and other symptoms, should promptly seek medical advice and treatment.