Nausea

Nausea is a complex sensation involving multiple body systems. It's controlled by the brain, specifically an area called the chemoreceptor trigger zone, which receives signals from various parts of the body including the digestive system, inner ear, and bloodstream. When these signals indicate something is wrong, you experience nausea.

While nausea often precedes vomiting, they are separate symptoms. You can have nausea without vomiting, and sometimes vomiting can occur with little warning. Nausea serves as a protective mechanism, discouraging you from eating when your body needs to focus on dealing with an illness or toxin.

The sensation can vary from person to person and situation to situation. Some describe it as a wave-like feeling, others as a constant queasiness. It may be accompanied by increased saliva production, dizziness, or a general feeling of being unwell.

Digestive System Causes

• Gastroenteritis: Stomach flu causing nausea, vomiting, and diarrhea
• GERD: Acid reflux causing nausea, especially after eating
• Food poisoning: Contaminated food causing sudden nausea and vomiting
• Gallstones: Can cause nausea, especially after fatty meals
• Peptic ulcers: Stomach or duodenal ulcers causing pain and nausea
• Appendicitis: Often starts with nausea before abdominal pain
• IBS: Can cause nausea along with bowel symptoms
• Gastroparesis: Delayed stomach emptying causing chronic nausea

Pregnancy and Hormonal Causes

• Morning sickness: Affects up to 80% of pregnant women
• Hyperemesis gravidarum: Severe pregnancy nausea requiring treatment
• Menstruation: Hormonal changes can cause nausea
• Birth control pills: May cause nausea as side effect
• Menopause: Hormonal fluctuations can trigger nausea

Neurological Causes

• Migraines: Often accompanied by severe nausea
• Motion sickness: Inner ear disturbance from movement
• Vertigo: Dizziness causing secondary nausea
• Concussion: Head injury often causes nausea
• Increased intracranial pressure: From various causes
• Meningitis: Infection causing headache, fever, and nausea

Medications and Treatments

• Chemotherapy: Common side effect of cancer treatment
• Antibiotics: Can disturb stomach and cause nausea
• Pain medications: Especially opioids
• Anesthesia: Post-operative nausea is common
• Radiation therapy: Can cause nausea if abdomen involved
• Antidepressants: May cause nausea when starting

Systemic Conditions

• Infections: Flu, COVID-19, and other viral infections
• Diabetes: Especially with blood sugar fluctuations
• Kidney disease: Uremia can cause chronic nausea
• Liver disease: Advanced liver disease causes nausea
• Heart attack: Can present with nausea, especially in women
• Anxiety: Stress and panic can trigger nausea

Other Common Causes

• Overeating: Stomach distension causing discomfort
• Alcohol: Both intoxication and hangovers
• Food intolerances: Lactose intolerance, gluten sensitivity
• Strong odors: Perfumes, cooking smells, chemicals
• Pain: Severe pain from any cause
• Dehydration: Can cause or worsen nausea

Nausea rarely occurs alone. Common accompanying symptoms include:

• Vomiting: The forceful expulsion of stomach contents
• Increased salivation: Body preparing for potential vomiting
• Sweating: Cold sweats are common with nausea
• Dizziness: Feeling lightheaded or unsteady
• Headache: Especially with migraines
• Abdominal pain: Cramping or discomfort
• Loss of appetite: Food aversion
• Fatigue: Feeling weak or tired
• Pale skin: Due to blood flow changes
• Rapid heart rate: Stress response
• Diarrhea: With gastrointestinal causes
• Fever: If infection is present

See a Doctor Soon If You Have:

• Nausea lasting more than a week
• Unexplained weight loss
• Inability to keep fluids down for 24 hours
• Signs of dehydration (dark urine, dizziness)
• Nausea that interferes with daily activities
• Pregnancy with severe nausea
• Nausea after starting new medication
• Recurrent episodes without clear cause

General Prevention

• Identify triggers: Keep a diary of when nausea occurs
• Eat regularly: Don't skip meals or get too hungry
• Stay hydrated: Dehydration can cause nausea
• Manage stress: Practice relaxation techniques
• Get adequate sleep: Fatigue can trigger nausea
• Avoid known triggers: Certain foods, smells, or activities

Specific Situations

Motion Sickness Prevention

• Sit in front seat of car or over wing in plane
• Focus on horizon or distant object
• Avoid reading or screens while moving
• Get fresh air when possible
• Consider preventive medication

Morning Sickness Prevention

• Keep crackers by bedside
• Eat protein before bed
• Rise slowly in the morning
• Avoid empty stomach
• Stay hydrated

Medication-Related Nausea

• Take medications with food unless directed otherwise
• Ask about anti-nausea medication
• Time medications appropriately
• Discuss alternatives with doctor

When nausea is persistent or severe, doctors use various methods to find the cause:

Medical History

• Duration and pattern of nausea
• Associated symptoms
• Dietary habits and recent changes
• Medications and supplements
• Medical conditions
• Recent travel or exposures
• Pregnancy possibility

Physical Examination

• Vital signs check
• Abdominal examination
• Neurological assessment
• Signs of dehydration
• Ear examination (for vertigo)

Diagnostic Tests

• Blood tests: Check for infections, organ function
• Urine tests: Pregnancy test, kidney function
• Imaging: X-rays, CT scans, or ultrasound
• Endoscopy: To examine upper digestive tract
• Gastric emptying study: For suspected gastroparesis

For those dealing with ongoing nausea, these strategies can help maintain quality of life:

• Work with specialists: Gastroenterologist or other appropriate specialist
• Keep a symptom diary: Track patterns and triggers
• Nutritional support: Work with dietitian if needed
• Emotional support: Consider counseling for chronic illness
• Medication management: Find right combination with doctor
• Alternative therapies: Explore acupuncture, hypnotherapy
• Support groups: Connect with others experiencing similar issues
• Workplace accommodations: Discuss needs with employer