Propofol is an intravenous anesthetic used to produce relaxation and sleep before or during surgery, as well as in patients on a ventilator. It is also used for procedural sedation, during monitored anesthesia care, or as an induction agent for general anesthesia. Propofol is prepared in a lipid emulsion which gives it the characteristic milky white appearance and the colloquial name "milk of amnesia". It slows the activity of the brain and nervous system, causing a decreased level of consciousness. Propofol is used in adults as well as children 2 months and older. It is to be given only by or under the direct supervision of a doctor. Strict aseptic technique must be used when drawing up propofol as the emulsion can support microbial growth. Propofol should not be used in any patient unless they are appropriately fasting, and it should not be used in patients who are allergic to eggs, egg products, soybeans, or soy products. Propofol may cause side effects such as propofol infusion syndrome, which can lead to more serious problems, and it may also cause a dose-dependent decreased level of consciousness.