Ketosis generally refers to ketoacidosis, the symptoms of which are mainly the smell of rotten apples in the breath, nausea and vomiting, polyuria, dry mouth, loss of appetite, fatigue and weakness. Ketoacidosis, mainly due to the disorder of energy metabolism in the body, leading to the production of ketone bodies in large quantities, due to the accumulation in the body. Because of the large amount of ketone bodies in the body, especially acetone, the breath will have a rotten apple odor. Due to the disorder of energy metabolism in the body, there will be fatigue and weakness; due to the ketone body toxic substance stimulation, nausea and vomiting, dry mouth, loss of appetite and other symptoms. As ketone bodies lead to increased plasma osmolality, and due to the occurrence of osmotic diuresis, resulting in polyuria. Due to ketoacidosis will lead to a drop in blood volume, blood circulation disorders, the brain blood supply and oxygen supply is insufficient, so there will be drowsiness or even coma and other symptoms. For diabetics, if you suddenly notice a worsening of the symptoms of eating too much, drinking too much, urinating too much, and your breath smells like rotten apples, you should seek immediate medical attention, as it is likely that ketoacidosis has persisted. Ketoacidosis is an acute condition that can lead to death if not treated in time, so immediate medical attention is required to follow the doctor’s instructions for examination and treatment.