Long-term use of lidocaine can be harmful to the body in the following ways: 1. Nervous system: Patients can experience dizziness, vertigo, nausea, vomiting, lethargy, slurred speech, abnormal sensation, tremors, and convulsions. 2. Cardiovascular: The effects on patients are sinus bradycardia, cardiac arrest, severe atrioventricular block, and reduced myocardial contractility. 3. Respiratory system Aspects: If used topically, it may cause bronchospasm and adults may develop respiratory distress syndrome, but it is relatively rare. Long-term use of lidocaine, usually a topical cream, topical drugs have relatively few side effects, the most common is that it may cause skin allergies, in addition, long-term use will cause a certain degree of dependence.