Entonox is a pain-relieving gas mixed in the ratio 50:50 nitrous oxide (N₂O) and Oxygen (O₂). The gas is delivered to patients via inhalation by using a pressure regulator and demand valve. The gas is both highly effective and controllable in its effects with rapid onset and rapid recovery. It is an analgesic agent in first aid, emergency services, obstetrics, ambulances, nursing services and in medical and dental surgeries. ENTONOX® is both highly effective and controllable in its effects: Pain reliever for short-term pain including acute trauma, dental procedures, and other painful procedures such as childbirth, wound and burn dressing, wound debridement and suturing Does not accumulate to any great extent within the body Free from after-effects of the risk of overdose Compatible with all other analgesic or therapeutic drugs Compatible with all other analgesic or therapeutic drugs