Definition

Vomiting, also known as emesis, is the forceful expulsion of stomach contents through the mouth.

It is typically a reflexive action triggered by the vomiting center in the brainstem, specifically in the medulla oblongata. Vomiting can be caused by a variety of factors, including:

• Gastrointestinal irritation (e.g., infections, food poisoning, or obstructions)
• Neurological stimuli (e.g., motion sickness or migraines)
• Toxins or medications (e.g., alcohol, chemotherapy drugs)
• Systemic conditions (e.g., pregnancy, metabolic imbalances, or infections)

The process involves several steps:

1. Nausea (the sensation of needing to vomit, often accompanied by sweating and increased saliva production)
2. Retching (involuntary abdominal muscle contractions without expulsion of stomach contents)
3. Vomiting (forceful expulsion due to coordinated contraction of the diaphragm, abdominal muscles, and relaxation of the esophageal sphincter).

It is a protective mechanism to remove harmful substances or respond to various physiological disturbances.

 

Determining the Cause