Potassium deficiency generally refers to hypokalemia. Hypokalemia can have digestive system symptoms, muscle symptoms, cardiac arrhythmia, etc. Prompt medical treatment is recommended. 1. Digestive system symptoms: nausea, vomiting, abdominal distension, loss of appetite and other symptoms. 2. Muscle symptoms: Hyperpolarization of skeletal muscle cell membranes caused by hyperkalemia can affect the depolarization of cells, leading to contractile dysfunction. It is manifested as weakness and even muscle paralysis. 3. Arrhythmia: there may be symptoms of tachycardia and atrial or ventricular pre-systole in the early stage, and ventricular flutter and ventricular fibrillation in the severe cases. When symptoms similar to hypokalemia appear, it is recommended to go to the hospital in time.