Laughing Gas (1914 film) squabbling. The dentist arrives, and his first patient goes in, obviously in pain. The dentist prepares the nitrous oxide anaesthesic (also known commonly as "laughing gas" due to its effects prior to and after unconsciousness). With the man unconscious he pulls his tooth, but then he can't get him to wake up. He calls for Charlie and when he arrives the dentist runs off. Charlie tries to wake him and eventually tries hitting his head with a mallet. The man revives but starts laughing. Charlie knocks him out with the mallet. The dentist then returns and Charlie is sent to
Substance dependence upon which a person has developed a dependence syndrome. When dependence has developed, cessation of substance use produces an unpleasant state, which promotes continued drug use through negative reinforcement; i.e., the drug is used to escape or avoid re-entering the associated withdrawal state. The withdrawal state may include physical-somatic symptoms (physical dependence), emotional-motivational symptoms (psychological dependence), or both. Chemical and hormonal imbalances may arise if the substance is not introduced. Psychological stress may also result if the substance is not re-introduced. Infants also suffer from substance withdrawal, known as Neonnatal Abstinence Syndrome (NAS) which has severe and life-threatening effects on