Cause of Vomition

Vomition (vomiting) is caused by:

Correct Answer: Reverse peristalsis

Vomition (vomiting) is caused by reverse peristalsis — the normal direction of peristaltic contractions reverses, propelling stomach and duodenal contents upward and out through the mouth.

Normal GIT Motility

• Peristalsis: Rhythmic wave-like contractions moving ingesta in the forward direction (mouth → rectum). This is the primary propulsive movement.
• Segmentation: Localized contractions that mix ingesta without net forward movement.
• Pendular movements: Back-and-forth movement; mixing and some propulsion.
• Food movement forward = Peristalsis + Segmentation + Pendular movements

Vomiting Centre

• Located in the medulla oblongata.
• Ruminants rarely vomit (due to the forestomach design), but horses and rats cannot vomit at all.