Vomiting Health Channel

Definition

Nausea is the sensation of having an urge to vomit. Vomiting is forcing the contents of the stomach up through the esophagus and out of the mouth.

Alternative Names

Emesis; Vomiting; Stomach upset; Upset stomach

Considerations

Your body has a few main ways to respond to an ever-changing, wide variety of invaders and irritants. Sneezing ejects the intruders from the nose, coughing from the lungs and throat, diarrhea from the intestines, and vomiting from the stomach.

Vomiting is a forceful action accomplished by a fierce, downward contraction of the diaphragm. At the same time, the abdominal muscles tighten against a relaxed stomach with an open sphincter. The contents of the stomach are propelled up and out.

You may have more saliva just before vomiting.

Vomiting is a complex, coordinated reflex orchestrated by the vomiting center of the brain. It responds to signals coming from:

• The mouth, stomach, and intestines
• The bloodstream, which may contain medicines or infections
• The balancing systems in the ear (motion sickness)
• The brain itself, including unsettling sights, smells, or thoughts

An amazing variety of stimuli can trigger vomiting, from migraines to kidney stones. Sometimes, just seeing someone else vomit will start you vomiting, in your body's effort to protect you from possible exposure to the same danger.

Vomiting is common. Almost all children will vomit several times during their childhood. In most cases, it is due to a viral gastrointestinal infection.

“Spitting up,” the gentle sloshing of stomach contents up and out of the mouth, sometimes with a burp, is an entirely different process.