emétogènes

Emétogènes are agents that induce the sensation of nausea and provoke vomiting. They can be endogenous, such as neurotransmitters released during a stress response, or exogenous, including chemicals, drugs, or environmental toxins. The emetic reflex is mediated primarily by the chemoreceptor trigger zone (CTZ) in the medulla and the vomiting center in the brainstem. When these areas are stimulated, signals are sent through the autonomic nervous system to muscles involved in the vomiting process.

Common pharmacologic emétogènes encompass chemotherapeutic agents (cisplatin, doxorubicin), opioids such as morphine, and anti‑emetic drugs used in allergic reactions (hydroxychloroquine). Non‑pharmacologic culprits include electromagnetic radiation from diagnostic imaging, radiation therapy, and certain foods or beverages that cause gastric irritation. Chemical toxins, such as ethanol, methanol, and cyanide, also possess strong emetic properties. Environmental factors like strong odors, low air quality, or abrupt temperature changes can trigger vomiting in sensitive individuals.

Clinical management focuses on identifying the underlying cause, replacing fluids and electrolytes, and administering anti‑emetic medications. Common drugs used are ondansetron, granisetron, and ondansetron, acting on serotonin receptors; prochlorperazine targets dopamine receptors. In severe cases, surgical or gastrointestinal interventions may be necessary. Avoidance strategies include dietary modifications, limiting exposure to known emétogènes, and using protective equipment during diagnostic procedures. Early recognition and treatment of emetogenic exposures reduce morbidity, prevent dehydration, and improve patient outcomes.