Drugs given usually during a surgical procedure to keep patients from feeling pain during surgery. There are several types of anesthesia: local anesthesia (numbing medicine) is injected in the area of the surgical procedure; regional anesthesia usually numbs up a large region of the body such as the legs or lower abdomenl; and general anesthesia where the patient is usually completely asleep. Regional and general anesthesia is usually administered by an anesthesiologist. Local anesthesia is usually administered by the surgeon.