náusees

Náusees, commonly written as náuseas in Spanish and Portuguese, is the subjective sensation of an uneasy stomach with an urge to vomit. It may occur with or without actual vomiting and is a symptom rather than a disease. It is a frequent reason for medical consultation and occurs in many contexts, including pregnancy, illness, medication use, and motion or stress.

Causes of náusees cover a wide range. Common examples include pregnancy; acute gastroenteritis and other infections; motion sickness; functional disorders such as gastroparesis; medications including chemotherapeutic agents, analgesics, and antibiotics; metabolic disturbances such as ketoacidosis or uremia; and central nervous system disorders like migraine, concussion, and anxiety. Alarm symptoms—severe abdominal pain, vomiting blood, fever, dehydration, confusion, chest pain, or signs of dehydration—require urgent evaluation to exclude serious conditions.

Pathophysiology involves the integration of signals in the brain and autonomic nervous system. The chemoreceptor trigger zone, vestibular system, gastrointestinal tract, and higher cortical centers can trigger náusees through neurotransmitters such as serotonin, dopamine, histamine, and acetylcholine.

Diagnosis is typically clinical, based on history and physical examination. Most cases are self-limited, with targeted tests used when a specific illness is suspected or red flags appear.

Treatment focuses on the underlying cause and supportive care. Antiemetic medications include 5-HT3 receptor antagonists (ondansetron), dopamine antagonists (metoclopramide, prochlorperazine), antihistamines (dimenhydrinate), and anticholinergics (scopolamine). Nonpharmacologic measures include oral hydration, small meals, bland foods, ginger, and avoiding strong odors. In pregnancy, healthcare providers may recommend pyridoxine (vitamin B6) with doxylamine or other approved options.