There are several possible diseases of generalized muscle atrophy: 1. Familial amyotrophic lateral sclerosis, which is mostly a family genetic disease. The main performance is the initial feeling of weakness, fatigue, gradually appearing whole body muscle atrophy and swallowing difficulties, and finally even develop into respiratory failure. 2, myasthenia gravis, the performance of myasthenia gravis is mainly the upper eyelid drooping, swallowing difficulties, breathing difficulties, limb weakness, morning light curtain heavy symptoms for the first, and then gradually develop into whole body muscle atrophy, respiratory failure. 3, malignant tumor, whole body muscle atrophy if it is sudden condition, do not exclude the possibility of malignant tumor, such as bone malignant tumor. Because malignant tumor is a consumptive disease, it may cause sudden muscle atrophy of the whole body. It is recommended to immediately consult a regular hospital, improve the relevant examination, and clarify the cause as soon as possible after the next step of treatment.