{"id":5340,"date":"2025-12-08T13:54:07","date_gmt":"2025-12-08T18:54:07","guid":{"rendered":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/?post_type=chapter&p=5340"},"modified":"2026-01-12T18:38:54","modified_gmt":"2026-01-12T23:38:54","slug":"vomiting-emesis","status":"web-only","type":"chapter","link":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/chapter\/vomiting-emesis\/","title":{"raw":"10p2 Vomiting (Emesis)","rendered":"10p2 Vomiting (Emesis)"},"content":{"raw":"Vomiting (Emesis) \u2013 The Body\u2019s Defense Mechanism<\/strong>\r\n

Overview<\/strong><\/h1>\r\n
    \r\n \t
  • Vomiting is an involuntary reflex (emetic reflex<\/strong>) designed to protect the body.<\/li>\r\n \t
  • Purpose: Rapidly remove irritants, toxins, or pathogens from the gastrointestinal (GI) tract.<\/li>\r\n<\/ul>\r\n

    Causes of Vomiting<\/strong><\/h1>\r\n
      \r\n \t
    • Consumption of\u00a0bad food<\/strong>\u00a0or\u00a0infected food<\/strong>.<\/li>\r\n \t
    • Ingestion of\u00a0poisons<\/strong>\u00a0or\u00a0toxins<\/strong>.<\/li>\r\n \t
    • Gastrointestinal infections<\/strong>.<\/li>\r\n \t
    • Medications<\/strong>\u00a0or\u00a0drugs<\/strong>.<\/li>\r\n \t
    • Physical stimuli<\/strong>\u00a0like\u00a0distention<\/strong>\u00a0or\u00a0irritation<\/strong>\u00a0of the stomach.<\/li>\r\n \t
    • Sensory triggers:\r\n
        \r\n \t
      • Bad smells<\/strong>.<\/li>\r\n \t
      • Pain<\/strong>.<\/li>\r\n \t
      • Visual stimuli<\/strong>.<\/li>\r\n<\/ul>\r\n<\/li>\r\n \t
      • Inner ear (vestibular apparatus)<\/strong>\u00a0triggers (motion sickness).<\/li>\r\n \t
      • Increased intracranial pressure (ICP)<\/strong>\u00a0causes early, forceful vomiting.<\/li>\r\n<\/ul>\r\n

        Neural Control<\/strong><\/h1>\r\n
          \r\n \t
        • The\u00a0medulla oblongata<\/strong>, specifically the\u00a0emetic center<\/strong>, orchestrates vomiting.<\/li>\r\n \t
        • Chemoreceptors detect irritants\/signals and activate this center.<\/li>\r\n<\/ul>\r\n

          The Vomiting Reflex<\/strong><\/h1>\r\n
            \r\n \t
          • Involves coordination of\u00a0smooth muscle<\/strong>\u00a0in the stomach and intestines.<\/li>\r\n \t
          • Results in\u00a0forceful expulsion<\/strong>\u00a0of stomach contents.<\/li>\r\n \t
          • Contents may include\u00a0bile<\/strong>\u00a0and intestinal contents if severe.<\/li>\r\n<\/ul>\r\n

            Complications of Prolonged Vomiting<\/strong><\/h1>\r\n
              \r\n \t
            • Dehydration<\/strong>:\r\n
                \r\n \t
              • Loss of fluids leads to\u00a0hypovolemia<\/strong>.<\/li>\r\n \t
              • Results in\u00a0low blood pressure<\/strong>,\u00a0paleness<\/strong>,\u00a0weakness<\/strong>.<\/li>\r\n<\/ul>\r\n<\/li>\r\n \t
              • Electrolyte imbalances<\/strong>:\r\n
                  \r\n \t
                • Loss of\u00a0hydrogen ions<\/strong>\u00a0(acidic gastric fluid) can make bodily fluids\u00a0more basic<\/strong>.<\/li>\r\n \t
                • Loss of\u00a0sodium, potassium,<\/strong>\u00a0and\u00a0chloride<\/strong>.<\/li>\r\n<\/ul>\r\n<\/li>\r\n \t
                • Nutritional deficiencies<\/strong>\u00a0leading to\u00a0malnourishment<\/strong>.<\/li>\r\n \t
                • Salivation<\/strong>\u00a0increases reflexively to protect oral tissues.<\/li>\r\n<\/ul>\r\n

                  Physiological Signs of Stress<\/strong><\/h1>\r\n
                    \r\n \t
                  • SNS activation<\/strong>:\r\n
                      \r\n \t
                    • Vasoconstriction<\/strong>\u00a0(pale skin).<\/li>\r\n \t
                    • Sweating.<\/li>\r\n \t
                    • Tachycardia<\/strong>\u00a0(fast heart rate).<\/li>\r\n \t
                    • Feeling\u00a0distressed<\/strong>\u00a0and\u00a0anxious<\/strong>.<\/li>\r\n<\/ul>\r\n<\/li>\r\n<\/ul>\r\n

                      Causes and Triggers<\/strong><\/h1>\r\n
                        \r\n \t
                      • Overeating or food intolerances.<\/li>\r\n \t
                      • Infections<\/strong>\u00a0or inflammation.<\/li>\r\n \t
                      • Psychological triggers<\/strong>\u00a0(e.g., nausea from distress).<\/li>\r\n \t
                      • Motion sickness<\/strong>:\r\n
                          \r\n \t
                        • Inner ear sensors detect movement, conflicting visual input causes nausea.<\/li>\r\n<\/ul>\r\n<\/li>\r\n \t
                        • Increased intracranial pressure (ICP)<\/strong>:\r\n
                            \r\n \t
                          • Causes\u00a0early, forceful projectile vomiting<\/strong>.<\/li>\r\n<\/ul>\r\n<\/li>\r\n \t
                          • Pregnancy<\/strong>:\r\n
                              \r\n \t
                            • Hormonal changes may trigger\u00a0morning sickness<\/strong>.<\/li>\r\n<\/ul>\r\n<\/li>\r\n \t
                            • Poisoning or toxins<\/strong>.<\/li>\r\n \t
                            • Blood in vomit (hematemesis)<\/strong>:\r\n
                                \r\n \t
                              • Bright red indicates recent bleeding.<\/li>\r\n \t
                              • Coffee-ground<\/strong>\u00a0appearance suggests older blood digestion.<\/li>\r\n<\/ul>\r\n<\/li>\r\n \t
                              • Obstructions<\/strong>\u00a0or\u00a0infection<\/strong>\u00a0may cause recurrent vomiting.<\/li>\r\n<\/ul>\r\n

                                Signs of Serious Conditions<\/strong><\/h1>\r\n
                                  \r\n \t
                                • Blood in vomit<\/strong>:\r\n
                                    \r\n \t
                                  • Hematemesis<\/strong>\u00a0(fresh blood).<\/li>\r\n \t
                                  • Coffee ground<\/strong>\u00a0vomitus.<\/li>\r\n<\/ul>\r\n<\/li>\r\n \t
                                  • Green or yellow tinge<\/strong>:\r\n
                                      \r\n \t
                                    • Indicative of bile, possibly from lower GI or intestinal obstruction.<\/li>\r\n<\/ul>\r\n<\/li>\r\n \t
                                    • Unconsciousness<\/strong>:\r\n
                                        \r\n \t
                                      • Possible spinal injury.<\/li>\r\n \t
                                      • Immediate stabilization and hospital care needed.<\/li>\r\n<\/ul>\r\n<\/li>\r\n<\/ul>\r\n

                                        Emergency Response<\/strong><\/h1>\r\n
                                          \r\n \t
                                        • Protect the airway, especially if unconscious.<\/li>\r\n \t
                                        • Spinal precautions if trauma suspected.<\/li>\r\n \t
                                        • Transport to hospital immediately.<\/li>\r\n \t
                                        • Ensure\u00a0airway<\/strong>\u00a0and\u00a0breathing<\/strong>\u00a0are secure.<\/li>\r\n<\/ul>\r\n

                                          Summary<\/strong><\/h1>\r\n
                                            \r\n \t
                                          • Vomiting is a\u00a0protective reflex<\/strong>\u00a0but can cause serious electrolyte imbalance, dehydration, and injury.<\/li>\r\n \t
                                          • Recognizing causes and signs of dangerous vomiting is essential for prompt medical intervention.<\/li>\r\n<\/ul>","rendered":"

                                            Vomiting (Emesis) \u2013 The Body\u2019s Defense Mechanism<\/strong><\/p>\n

                                            Overview<\/strong><\/h1>\n
                                              \n
                                            • Vomiting is an involuntary reflex (emetic reflex<\/strong>) designed to protect the body.<\/li>\n
                                            • Purpose: Rapidly remove irritants, toxins, or pathogens from the gastrointestinal (GI) tract.<\/li>\n<\/ul>\n

                                              Causes of Vomiting<\/strong><\/h1>\n
                                                \n
                                              • Consumption of\u00a0bad food<\/strong>\u00a0or\u00a0infected food<\/strong>.<\/li>\n
                                              • Ingestion of\u00a0poisons<\/strong>\u00a0or\u00a0toxins<\/strong>.<\/li>\n
                                              • Gastrointestinal infections<\/strong>.<\/li>\n
                                              • Medications<\/strong>\u00a0or\u00a0drugs<\/strong>.<\/li>\n
                                              • Physical stimuli<\/strong>\u00a0like\u00a0distention<\/strong>\u00a0or\u00a0irritation<\/strong>\u00a0of the stomach.<\/li>\n
                                              • Sensory triggers:\n
                                                  \n
                                                • Bad smells<\/strong>.<\/li>\n
                                                • Pain<\/strong>.<\/li>\n
                                                • Visual stimuli<\/strong>.<\/li>\n<\/ul>\n<\/li>\n
                                                • Inner ear (vestibular apparatus)<\/strong>\u00a0triggers (motion sickness).<\/li>\n
                                                • Increased intracranial pressure (ICP)<\/strong>\u00a0causes early, forceful vomiting.<\/li>\n<\/ul>\n

                                                  Neural Control<\/strong><\/h1>\n
                                                    \n
                                                  • The\u00a0medulla oblongata<\/strong>, specifically the\u00a0emetic center<\/strong>, orchestrates vomiting.<\/li>\n
                                                  • Chemoreceptors detect irritants\/signals and activate this center.<\/li>\n<\/ul>\n

                                                    The Vomiting Reflex<\/strong><\/h1>\n
                                                      \n
                                                    • Involves coordination of\u00a0smooth muscle<\/strong>\u00a0in the stomach and intestines.<\/li>\n
                                                    • Results in\u00a0forceful expulsion<\/strong>\u00a0of stomach contents.<\/li>\n
                                                    • Contents may include\u00a0bile<\/strong>\u00a0and intestinal contents if severe.<\/li>\n<\/ul>\n

                                                      Complications of Prolonged Vomiting<\/strong><\/h1>\n
                                                        \n
                                                      • Dehydration<\/strong>:\n
                                                          \n
                                                        • Loss of fluids leads to\u00a0hypovolemia<\/strong>.<\/li>\n
                                                        • Results in\u00a0low blood pressure<\/strong>,\u00a0paleness<\/strong>,\u00a0weakness<\/strong>.<\/li>\n<\/ul>\n<\/li>\n
                                                        • Electrolyte imbalances<\/strong>:\n
                                                            \n
                                                          • Loss of\u00a0hydrogen ions<\/strong>\u00a0(acidic gastric fluid) can make bodily fluids\u00a0more basic<\/strong>.<\/li>\n
                                                          • Loss of\u00a0sodium, potassium,<\/strong>\u00a0and\u00a0chloride<\/strong>.<\/li>\n<\/ul>\n<\/li>\n
                                                          • Nutritional deficiencies<\/strong>\u00a0leading to\u00a0malnourishment<\/strong>.<\/li>\n
                                                          • Salivation<\/strong>\u00a0increases reflexively to protect oral tissues.<\/li>\n<\/ul>\n

                                                            Physiological Signs of Stress<\/strong><\/h1>\n
                                                              \n
                                                            • SNS activation<\/strong>:\n
                                                                \n
                                                              • Vasoconstriction<\/strong>\u00a0(pale skin).<\/li>\n
                                                              • Sweating.<\/li>\n
                                                              • Tachycardia<\/strong>\u00a0(fast heart rate).<\/li>\n
                                                              • Feeling\u00a0distressed<\/strong>\u00a0and\u00a0anxious<\/strong>.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n

                                                                Causes and Triggers<\/strong><\/h1>\n
                                                                  \n
                                                                • Overeating or food intolerances.<\/li>\n
                                                                • Infections<\/strong>\u00a0or inflammation.<\/li>\n
                                                                • Psychological triggers<\/strong>\u00a0(e.g., nausea from distress).<\/li>\n
                                                                • Motion sickness<\/strong>:\n
                                                                    \n
                                                                  • Inner ear sensors detect movement, conflicting visual input causes nausea.<\/li>\n<\/ul>\n<\/li>\n
                                                                  • Increased intracranial pressure (ICP)<\/strong>:\n
                                                                      \n
                                                                    • Causes\u00a0early, forceful projectile vomiting<\/strong>.<\/li>\n<\/ul>\n<\/li>\n
                                                                    • Pregnancy<\/strong>:\n
                                                                        \n
                                                                      • Hormonal changes may trigger\u00a0morning sickness<\/strong>.<\/li>\n<\/ul>\n<\/li>\n
                                                                      • Poisoning or toxins<\/strong>.<\/li>\n
                                                                      • Blood in vomit (hematemesis)<\/strong>:\n
                                                                          \n
                                                                        • Bright red indicates recent bleeding.<\/li>\n
                                                                        • Coffee-ground<\/strong>\u00a0appearance suggests older blood digestion.<\/li>\n<\/ul>\n<\/li>\n
                                                                        • Obstructions<\/strong>\u00a0or\u00a0infection<\/strong>\u00a0may cause recurrent vomiting.<\/li>\n<\/ul>\n

                                                                          Signs of Serious Conditions<\/strong><\/h1>\n
                                                                            \n
                                                                          • Blood in vomit<\/strong>:\n
                                                                              \n
                                                                            • Hematemesis<\/strong>\u00a0(fresh blood).<\/li>\n
                                                                            • Coffee ground<\/strong>\u00a0vomitus.<\/li>\n<\/ul>\n<\/li>\n
                                                                            • Green or yellow tinge<\/strong>:\n
                                                                                \n
                                                                              • Indicative of bile, possibly from lower GI or intestinal obstruction.<\/li>\n<\/ul>\n<\/li>\n
                                                                              • Unconsciousness<\/strong>:\n
                                                                                  \n
                                                                                • Possible spinal injury.<\/li>\n
                                                                                • Immediate stabilization and hospital care needed.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n

                                                                                  Emergency Response<\/strong><\/h1>\n
                                                                                    \n
                                                                                  • Protect the airway, especially if unconscious.<\/li>\n
                                                                                  • Spinal precautions if trauma suspected.<\/li>\n
                                                                                  • Transport to hospital immediately.<\/li>\n
                                                                                  • Ensure\u00a0airway<\/strong>\u00a0and\u00a0breathing<\/strong>\u00a0are secure.<\/li>\n<\/ul>\n

                                                                                    Summary<\/strong><\/h1>\n
                                                                                      \n
                                                                                    • Vomiting is a\u00a0protective reflex<\/strong>\u00a0but can cause serious electrolyte imbalance, dehydration, and injury.<\/li>\n
                                                                                    • Recognizing causes and signs of dangerous vomiting is essential for prompt medical intervention.<\/li>\n<\/ul>\n","protected":false},"author":1370,"menu_order":5,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":["zoe-soon"],"pb_section_license":"cc-by-nc-sa"},"chapter-type":[],"contributor":[60],"license":[57],"class_list":["post-5340","chapter","type-chapter","status-web-only","hentry","contributor-zoe-soon","license-cc-by-nc-sa"],"part":67,"_links":{"self":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters\/5340","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/users\/1370"}],"version-history":[{"count":3,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters\/5340\/revisions"}],"predecessor-version":[{"id":5343,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters\/5340\/revisions\/5343"}],"part":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/parts\/67"}],"metadata":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters\/5340\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/media?parent=5340"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapter-type?post=5340"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/contributor?post=5340"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/license?post=5340"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}