Nausea and vomiting: Causes and how to stop them


Nausea and vomiting are common symptoms that can arise from a multitude of causes, ranging from benign to potentially severe. They are the body’s reflex actions to remove harmful substances, but they can also be triggered by various non-toxic causes. This article will explore the primary causes of nausea and vomiting, aiming to provide a comprehensive overview for healthcare professionals and patients alike.

1. Gastrointestinal Disorders

Gastrointestinal disorders are a significant cause of nausea and vomiting, affecting the digestive tract from the mouth to the intestines. Various conditions within this category can lead to these symptoms, each with unique causes, mechanisms, and treatments. Here, we’ll delve deeper into some of the primary gastrointestinal disorders that can cause nausea and vomiting, emphasizing their pathophysiology, diagnosis, and management strategies.


  • Pathophysiology: Gastroenteritis, often termed “stomach flu,” involves the inflammation of the stomach and intestines. Viral infections, most commonly caused by norovirus and rotavirus, are the leading cause. Bacterial infections, such as those caused by Salmonella, E. coli, and Campylobacter, are less common but can be more severe. The pathogens disrupt the normal absorption and secretion processes in the GI tract, leading to symptoms.
  • Diagnosis: Clinical assessment, including patient history and symptomatology, is usually sufficient for diagnosis. Stool cultures and rapid antigen tests may be used in severe cases or when a specific pathogen is suspected.
  • Management: Treatment focuses on hydration and electrolyte balance restoration. Oral rehydration solutions are preferred, and in severe cases, intravenous fluids may be necessary. Antimicrobials are prescribed in specific bacterial or parasitic infections.

Peptic Ulcers

  • Pathophysiology: Peptic ulcers occur when the stomach’s or small intestine’s protective lining is eroded by stomach acid. This is often due to an infection with Helicobacter pylori or prolonged use of NSAIDs. The erosion causes pain and can lead to nausea and vomiting.
  • Diagnosis: Diagnosis involves endoscopy for direct visualization of the ulcer and testing for H. pylori infection through EGD, breath, blood, or stool tests.
  • Management: Treatment includes proton pump inhibitors (PPIs) to reduce acid production, antibiotics to treat H. pylori infection, and lifestyle modifications such as avoiding NSAIDs and smoking.

Gastroesophageal Reflux Disease (GERD)

  • Pathophysiology: GERD occurs when stomach acid frequently flows back into the esophagus. This backwash (acid reflux) can irritate the lining of the esophagus, causing nausea and vomiting among other symptoms.
  • Diagnosis: GERD is often diagnosed based on symptoms and response to acid-suppressing medications. Endoscopy, esophageal pH monitoring, and esophageal manometry may be used for further evaluation.
  • Management: Lifestyle changes, such as dietary modifications, weight loss, and elevating the head of the bed, are recommended. Medications like PPIs and H2 receptor antagonists can reduce acid production. In severe cases, surgical interventions may be considered.


  • Pathophysiology: Gastroparesis is a disorder characterized by delayed gastric emptying in the absence of mechanical obstruction. It’s often associated with diabetes, viral infections, and surgeries. The stomach’s muscles don’t function normally, causing nausea, vomiting, and other digestive symptoms.
  • Diagnosis: Gastroparesis is diagnosed using gastric emptying studies, which measure how quickly food leaves the stomach. Endoscopy and manometry may also be used to rule out other conditions.
  • Management: Dietary modifications, such as eating smaller and more frequent meals, can help manage symptoms. Medications that stimulate stomach muscle movements, like metoclopramide, may be prescribed. In severe cases, feeding tubes or gastric electrical stimulation might be necessary.

How to stop nausea and vomiting associated with gastrointestinal disorders?

Managing nausea and vomiting associated with gastrointestinal (GI) disorders involves a combination of medications, lifestyle adjustments, and, in some cases, treating the underlying condition. Here’s a detailed approach to alleviate these symptoms:


  • Antiemetics: These drugs are specifically designed to suppress nausea and vomiting. Examples include ondansetron, promethazine, and metoclopramide. They work by blocking neurotransmitters in the brain that trigger the vomiting reflex.
  • Proton Pump Inhibitors (PPIs) and H2 Receptor Antagonists: For conditions like GERD and peptic ulcers, reducing stomach acid can help alleviate symptoms. Medications such as omeprazole and famotidine decrease stomach acid production.
  • Antibiotics: If a bacterial infection (like H. pylori in peptic ulcers) is causing the symptoms, antibiotics can clear the infection and thereby reduce symptoms.
  • Prokinetics: In conditions like gastroparesis, prokinetic agents such as metoclopramide can help speed up gastric emptying, reducing nausea and vomiting.

Dietary Changes (What to eat and drink after vomiting)

  • Eat Smaller, More Frequent Meals: Large meals can exacerbate symptoms. Instead, opt for smaller portions eaten more frequently throughout the day.
  • Avoid Trigger Foods: Spicy, fatty, and acidic foods can worsen GI symptoms. Identify and avoid foods that trigger your symptoms.
  • Stay Hydrated: Drink clear or ice-cold beverages and avoid caffeine. Sip liquids slowly throughout the day to maintain hydration without triggering nausea.
  • Ginger: Some studies suggest that ginger can effectively reduce nausea. It can be consumed in various forms, such as ginger tea, candies, or supplements.

Lifestyle Modifications

  • Avoid Lying Down After Eating: For individuals with GERD or acid reflux, staying upright for at least 30 minutes after meals can reduce the risk of symptoms.
  • Stress Management: Stress and anxiety can exacerbate GI symptoms. Techniques such as meditation, yoga, and deep-breathing exercises can help manage stress levels.
  • Stop Smoking and Limit Alcohol: Both smoking and alcohol can irritate the GI tract and worsen symptoms.

Treating the Underlying Condition

  • Control Diabetes: For gastroparesis related to diabetes, controlling blood sugar levels can mitigate symptoms.
  • Surgery: In rare cases, surgical intervention may be necessary to correct structural issues or remove blockages in the GI tract.

When to See a Doctor

It’s essential to consult with gastroenterologist Dr. Zavos if nausea and vomiting are persistent, severe, or accompanied by other symptoms such as pain, fever, or signs of dehydration. They can provide a tailored treatment plan based on the specific GI disorder and individual health needs.

Effective management of nausea and vomiting related to GI disorders often requires a multifaceted approach, including medical treatment, dietary adjustments, and lifestyle changes. By addressing the underlying condition and employing strategies to control symptoms, individuals can significantly improve their quality of life.

2. Central Nervous System Causes

The central nervous system (CNS) plays a crucial role in the control of nausea and vomiting. Conditions affecting the CNS that may cause these symptoms include:

  • Migraines: Severe, throbbing headaches that are often accompanied by nausea and sensitivity to light and sound.
  • Brain Tumors: Masses or growths of abnormal cells in the brain can increase pressure and lead to nausea and vomiting.
  • Meniere’s Disease: A disorder of the inner ear that can lead to dizzy spells (vertigo) and hearing loss.

3. Medication-Induced

Many medications can cause nausea and vomiting as side effects, especially when they are first started or when taken in high doses. These include:

  • Chemotherapy drugs
  • Antibiotics
  • NSAIDs
  • Opioids
  • Certain antidepressants

4. Psychological Factors

Psychological factors, including stress, anxiety, and eating disorders such as bulimia nervosa, can also lead to nausea and vomiting. The body’s response to stress can trigger the vomiting center in the brain, leading to these symptoms.

5. Pregnancy

Nausea and vomiting, often referred to as morning sickness, are common in early pregnancy. The exact cause is unknown, but it is thought to be related to the increase in hormones, especially human chorionic gonadotropin (hCG).

6. Metabolic and Endocrine Issues

Conditions that disrupt the normal metabolism of the body can lead to nausea and vomiting. These include:

  • Hyperthyroidism
  • Diabetes (especially if poorly controlled)
  • Addison’s disease
  • Kidney failure

7. Cyclic vomiting syndrome

Cyclic vomiting syndrome (CVS) is a chronic functional disorder characterized by recurrent, episodic vomiting episodes that last for hours or days, separated by periods of normal health. This condition can affect individuals of any age, though it often begins in childhood. The exact cause of CVS is not fully understood, but it is thought to involve a combination of factors, including genetic predisposition, nervous system issues, and hormonal imbalances. Here, we delve into the pathophysiology, diagnosis, and management strategies for cyclic vomiting syndrome.


The underlying mechanisms of CVS are not entirely clear, but several theories have been proposed to explain its occurrence:

  • Mitochondrial Dysfunction: Some individuals with CVS have been found to have mitochondrial DNA mutations, suggesting a link between mitochondrial function and the syndrome.
  • Autonomic Nervous System Dysfunction: Dysregulation in the autonomic nervous system may lead to abnormal gastrointestinal motility and sensitivity, contributing to the episodes of vomiting.
  • Hormonal Influences: Fluctuations in hormones, particularly cortisol, have been observed in relation to vomiting episodes, indicating a potential hormonal component.
  • Migraine Connection: A significant overlap exists between CVS and migraines; both conditions may share similar pathophysiological mechanisms, such as serotonin dysregulation.


Diagnosing CVS can be challenging due to the lack of specific tests and the similarity of its symptoms to other conditions. Diagnosis is primarily clinical, based on the patient’s history and the exclusion of other causes. Criteria established by the Rome IV guidelines for CVS include:

  • A history of three or more episodes of acute nausea and vomiting lasting from hours to days, with intervening periods of normal health lasting weeks to months.
  • At least two of these episodes occurring in the past six months and at least one episode in the past three months.
  • Exclusion of other gastrointestinal or metabolic disorders that could explain the symptoms.

Further diagnostic tests, such as laboratory evaluations, imaging studies, and endoscopic examinations, may be performed to rule out other conditions.


Management of CVS focuses on preventing and treating episodes, as well as managing symptoms during episodes. Strategies include:

  • Medications: Prophylactic treatment with medications such as tricyclic antidepressants (e.g., amitriptyline) and anti-emetics may be used to prevent or reduce the frequency and severity of episodes. During episodes, medications to control nausea, vomiting, and pain are essential.
  • Lifestyle and Dietary Changes: Identifying and avoiding triggers for vomiting episodes, such as certain foods, stress, and intense physical activity, can be helpful. Maintaining a healthy lifestyle and stress management techniques, such as relaxation therapy and biofeedback, may also reduce episode frequency.
  • Hydration and Supportive Care: During episodes, maintaining hydration is crucial. This may require hospitalization for intravenous fluids and electrolytes in severe cases.


The course of CVS can vary widely among individuals. Some may experience a decrease in episode frequency or severity as they age, while others may continue to have episodes throughout their lives. In some cases, children with CVS may develop migraines later in life.


Nausea and vomiting are symptoms with a wide range of causes, from the relatively benign to those requiring immediate medical attention. Understanding the underlying cause is crucial for effective treatment. Patients experiencing persistent or severe symptoms should seek medical evaluation to determine the cause and appropriate treatment.

Last update: 10 April 2024, 22:17


Gastroenterologist - Hepatologist, Thessaloniki

PhD at Medical School, Aristotle University of Thessaloniki, Greece

PGDip at Universitair Medisch Centrum Utrecht, The Netherlands

Ex President, Hellenic H. pylori & Microbiota Study Group