Nausea and vomiting are commonly associated symptoms that can be caused by food poisoning, morning sickness, chemotherapy, or other medical issues. Nausea is an uneasiness in the stomach that often precedes vomiting, which is the forceful expulsion of stomach contents through the mouth. The pathophysiology of vomiting involves three phases - nausea, vomiting, and retching - which are triggered by impulses from the vomiting center in the brain to various muscles. Treatment options include non-drug approaches as well as pharmacological therapies that target receptors in the vomiting center and gastrointestinal tract, such as 5-HT3 receptor antagonists and antihistamines.

1. NAUSEA AND VOMITING

2. DEFINITION:
 NAUSEA: It is derived from the Greek word ”nautia” meaning sea sickness.
 NAUSEA is an uneasiness of the stomach that often come before vomiting.
 Vomiting is preceded by nausea.
 VOMITING: It is derived from the Latin word “vomere” meaning expulsion.
 Vomiting is the forcible voluntary or involuntory emptying (Throwing up) of
stomach content through the mouth.
 Nausea and vomiting are commonly associated symptoms.

3. ETIOLOGY
 Food allergies and food poisoning
 Motion sickness or sea sickness
 Cancer chemotherapy or radiation treatment
 Migraine headaches
 Infections of the stomach or bowels such as the “stomach flu”
 Morning sickness during pregnancy(Nausea occurs in approximately 50%to 90%
of all pregnancies but vomiting occurs in 25% to 55%.)
 GERD(Gastro oesophageal reflux disease)-It is a digestive disease in which
stomach acid or bile irritates the food pipe lining.)
 Nausea and vomiting may also be the early warning signs of serious medical
problems such as
1.Appendicitis
2.Cancer or a tumor
3.Ulcers in the lining of stomach or small intestine
4. blockage in the intestine

4. PATHOPHYSIOLOGY
The three consecutive phases of vomit emesis include
1.Nausea
2.Vomiting and
3.Retching
nausea(the imminent need to vomit)
associated with
gastric stasis(The stomach takes too long to empty its contents.)
retching(movement of abdominal and thoracic muscles before vomiting)
final phase: vomiting

5. PATHOPHYSIOLOGY
 Vomiting is triggered by afferent impulses which acts on the vomiting center
present in the middle.
 When excited afferent impulses integrated by the vomiting center resulting in
efferent impulses to the salvation center,respiratory center,pharyngeal,GI-
tract and abdominal muscles leading to vomiting.

6. PATHOPHYSIOLOGY
 The CTZ , is a major chemosensory organ for emesis and is usually associated
with chemically induced vomiting.
 Numerous neurotransmitter receptors are located in the vomiting centre ,
CTZ , and GI tract. Examples – Neurokinin,histaminit receptors.
 Theoretically, chemotherapeutic agents, their metabolites, or other emetic
compounds trigger the process of emesis through stimulation of one or more
receptors.
 If there is any toxic ingestion, stomach irritation results which triggers CTZ
receptor and induces vomiting.

8. TREATMENT
non drug treatment:
Patients with
simple
complaints
Related to food or
beverage
consumption
Avoidance or
moderation of
dietary intake
Due to
behavioral
interventions
Related to
emotions and
thoughts
Relaxation, guided
imagery,
systematic
desensitisation,
biofeedback

9. PHARMACOLOGICAL MANAGEMENT
Drug therapy
Antacids
* 5-HT3 receptor antagonists- ondansetron , palonsetron etc.
* Dopamine antagonist-domperidone,metoclopramide,olanzapine etc.
* NK1 receptor antagonist(neurokinin)-aprepitant,casopitant etc.
* Antihistamine(H1 histamine receptor antagonists)-
cyclizine,doxylamine,diphenhydramine etc.
* cannabinoids-nabilone ,cannabis ,dronabinol ,sativex etc.
* Anticholinergic-hyoscine
* Steroids-dexamethasone

10. Patient Education
 Eat salty food and avoid overly sweet ones especially if you being vomiting.
 Avoid liquid at meal times , take them after 30-60 mins after meal.
 Do not lie down flat for atleast two hours after eating
 Eat meal slowly .
 If the smell of food makes you nauseated, let someone else do the cooking or
use prepared food from the freezer.
 Do not consume food in a room filled with cooking odors or in a warm stuffy
room.
 Take clear cool beverages.