Changes

| 1800 || Field development || {{w|Humphry Davy}} observes "As nitrous oxide in its extensive operation appears capable of destroying physical pain, it may probably be used with advantage during surgical operations in which no great effusion of blood takes place."<ref name="History of Anesthesia"/> || {{w|United Kingdom}}

| 1804 || Drug || Japanese surgeon {{w|Hanaoka Seishū}} formulates his general anesthetic Tsusensan{{w|tsusensan}}.<ref name="History of Anesthesia"/> || {{w|Japan}}

| 1805 || Drug || German pharmacist {{w|Friedrich Sertürner}} isolates a new substance from {{w|opium}}, which he later names "morphium" after Morpheus, the god of dreams.<ref name="History of Anesthesia"/> || {{w|Germany}}

| 1818 || Field development || British scientist {{w|Michael Faraday}}, after studying the inhalation of {{w|ether}}, publishes his findings, including soporific and analgesic effects.<ref name="The History of Anaesthesiavvv"/> || {{w|United Kingdom}}

| 1824 || Field development || English physician {{w|Henry Hill Hickman}} describes carbon dioxide anesthesia for animals.<ref name="History of Anesthesia"/><ref name="A Dictionary of the History of Medicine">{{cite book |last1=Sebastian |first1=Anton |title=A Dictionary of the History of Medicine |url=https://books.google.com.ar/books?id=CvpKDwAAQBAJ&pg=PT420&lpg=PT420&dq=%221824%22+Henry+Hill+Hickman+(1800-1830)+describes+carbon+dioxide+anesthesia+for+animals.&source=bl&ots=xUTOXiKrLh&sig=6tXbVF6g7MayDkwHtjZObBy7t_4&hl=en&sa=X&ved=2ahUKEwieysWjw__cAhUMg5AKHSpSCrYQ6AEwA3oECAcQAQ#v=onepage&q=%221824%22%20Henry%20Hill%20Hickman%20(1800-1830)%20describes%20carbon%20dioxide%20anesthesia%20for%20animals.&f=false}}</ref> || {{w|United Kingdom}}

| 1829 || Field development || French physician {{w|Jules Germain Cloquet}} in {{w|Paris}} uses {{w|hypnosis}} for {{w|mastectomy}}.<ref name="History of anaesthesia"/><ref>{{cite journal |last1=Gravitz |first1=Melvin A. |title=Early Uses of Hypnosis as Surgical Anesthesia |journal=American Journal of Clinical Hypnosis |url=https://www.tandfonline.com/doi/abs/10.1080/00029157.1988.10402733}}</ref> || {{w|France}}

| 1831 || Drug || {{w|Chloroform}} is discovered independently by American physician [[w:Samuel Guthrie (physician)|Samuel Guthrie]], French scientist {{w|Eugène Soubeiran}}, and German chemist {{w|Justus von Liebig}}.<ref name="History of Anesthesia"/><ref>{{cite journal |last1=Wawersik |first1=J |title=[History of chloroform anesthesia]. |url=https://www.ncbi.nlm.nih.gov/pubmed/9487785}}</ref><ref>{{cite book |last1=Frost |first1=Elizabeth A.M. |title=Comprehensive Guide to Education in Anesthesia |url=https://books.google.com.ar/books?id=oQ4JAgAAQBAJ&pg=PA3&dq=%22in+1831%22+Chloroform&hl=en&sa=X&ved=0ahUKEwjx5uCF6LrdAhWGhJAKHdxjAtwQ6AEINjAC#v=onepage&q=%22in%201831%22%20Chloroform&f=false}}</ref><ref>{{cite book |last1=Barceloux |first1=Donald G. |title=Medical Toxicology of Drug Abuse: Synthesized Chemicals and Psychoactive Plants |url=https://books.google.com.ar/books?id=9JLiJcjdqkcC&pg=PA642&dq=%22in+1831%22+Chloroform&hl=en&sa=X&ved=0ahUKEwjx5uCF6LrdAhWGhJAKHdxjAtwQ6AEIOzAD#v=onepage&q=%22in%201831%22%20Chloroform&f=false}}</ref> || {{w|United States}}, {{w|France}}, {{w|Germany}}