Definition of Vomiting
- It is the forceful expulsion of stomach contents through the mouth.
- It is a protective reflex triggered by various stimuli and coordinated by the emetic center in the brainstem.
Common Causes
- Gastrointestinal irritation (e.g., food poisoning, infection)
- Motion sickness
- Pregnancy (morning sickness)
- Migraines
- Medications (e.g., chemotherapy, opioids)
- Psychological factors (e.g., stress, anxiety)
Types
| Type | Description | Associated Conditions |
| Projectile Vomiting | Sudden, forceful expulsion | Pyloric stenosis, CNS disorders |
| Regurgitation | Passive flow without force | GERD, achalasia |
| Nausea & Retching | Sensation of sickness & dry heaving | Motion sickness, anxiety |
| Bilious | Vomit contains bile (green/yellow) | Intestinal obstruction, gallbladder issues |
| Chronic | Persists > 2 weeks | Gastroparesis, cyclic vomiting syndrome |
Mechanism of Vomiting (Phases)
- Nausea – Sensation of unease and queasiness
- Retching – Dry heaves, contractions without expulsion
- Ejection – Forceful expulsion of stomach contents
- Recovery – Return to baseline
Triggered by stimuli affecting the GI tract, vestibular system, chemoreceptor trigger zone (CTZ), and cerebral cortex.
Advertisements
