What internal stimuli causes vomiting?

Internal stimuli that can trigger vomiting include the presence of toxins or irritants in the gastrointestinal tract, which activate the chemoreceptor trigger zone in the brain. Additionally, conditions such as severe pain, vestibular disorders (affecting balance), and certain hormonal changes can also stimulate the vomiting center in the brain. Other factors include infections, gastrointestinal obstructions, and motion sickness. These stimuli lead to the complex physiological response that results in vomiting.