Nitrous oxide is recognized as the safest sedative used in dentistry today. Nitrous Oxide is mixed with oxygen and inhaled through a small mask that fits over your nose to help you relax during dental treatment. It is mild, non-toxic and removes itself naturally from your body after use. It is even recommended for patients with certain medical conditions, including high blood pressure, angina and a history of heart attacks. Unlike general anaesthesia, patients on nitrous oxide will always remain fully conscious and responsive.