In the application of clinical anesthetics, the time for local anesthesia to expire is related to the type of anesthetic drug, and also to the physical condition of the individual patient using the drug. Usually it is two hours, not more than five hours will be invalidated. The time to expiration varies depending on the anesthetic drug used for local anesthesia. The type of anesthesia also affects the time to expiration. Usually intrathecal anesthesia will wear off in about two hours, and not more than five hours for those who have been under anesthesia for a longer period of time. Regional nerve block anesthesia has a shorter time frame and usually wears off between half an hour and two hours. The time to expiration of the same anesthesia medication varies from person to person and is related to body type. The clinical use of anesthesia drugs is very strict, and the time of expiration does not vary much. The anesthesiologist will keep an eye on the person using the medication for any adverse reactions.