The anesthesia used in liposuction varies, depending on the individual patient, the amount of fat to be removed and the surgeon's preferences. A fluid containing the anesthetic lidocaine, the drug epinephrine, which constricts blood vessels, and saline is infused into the area to be treated before the fat is suctioned off. Liposuction of small areas removing 1.5 liters of fat or less can be performed in an outpatient office surgical setting under the local anesthetic that is included in the solution. It is often combined with a sedative in pill form to keep the patient more relaxed during the procedure. If large amounts of fat are to be removed, such as more than 1.5 liters, and/or multiple areas of the body are to be treated, the procedure is usually performed on an outpatient basis in a hospital or an ambulatory surgery center under regional or general anesthesia. A regional anesthesia, such as an epidural block commonly used in childbirth, may be combined with intravenous sedation. With a general anesthesia, the patient is put to sleep. In cases involving general anesthesia and large areas of fat removal, patients may be hospitalized overnight.