Vomiting

Vomiting: A Powerful Cleansing Reflex

Vomiting (vomitus) is a forceful, reflexive expulsion of stomach contents through the mouth. Unlike nausea, which is a subjective sensation, vomiting is a complex physical act coordinated by the "vomiting center" in the brain. It is a powerful protective mechanism aimed at quickly removing toxins or irritants from the body. While vomiting can provide relief, it is an exhausting process, and its main danger, especially for children, lies in the risk of rapid dehydration.

Physiology of the vomiting act

The vomiting process is an amazingly coordinated sequence of actions:

1. It begins with a deep inhalation, the glottis closes to prevent vomitus from entering the airways.
2. The soft palate lifts to close the entrance to the nasal cavity.
3. A powerful, simultaneous contraction of the diaphragm and abdominal wall sharply increases intra‑abdominal pressure.
4. At the same time, the sphincter between the esophagus and stomach relaxes, and pressure literally "pushes" the stomach contents outward.

Causes that trigger vomiting

The vomiting center can be activated by many causes:

• Gastrointestinal infections (gastroenteritis): The most common cause. Viruses or bacteria irritate the stomach lining.
• Food poisoning: Reaction to toxins in food.
• Systemic infections: Especially in children, any infection with high fever can cause vomiting (fever with vomiting).
• Intestinal obstruction: Mechanical blockage of food passage. Vomiting in this case may have a green (with bile) color, which is a very alarming sign.
• Increased intracranial pressure: Head injuries, brain tumors.

Repeated vomiting leads to loss of not only water but also electrolytes, which can cause electrolyte imbalance.