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Nausea and vomiting

Nausea and vomiting

What are nausea and vomiting?

Nausea and vomiting are both symptoms of certain underlying conditions, and they commonly occur together.

Nausea is the term used for the feeling that you are about to be sick or vomit. It usually comes on quickly, and typical symptoms include a sudden awareness that your stomach feels uneasy, sweating, an unhealthy-looking pale appearance, a rush of saliva, and dizziness.

Vomiting is the forcible discharge of stomach contents through the mouth (also called “throwing up”). Although many cases of vomiting are preceded by nausea, nausea can occur by itself for long periods, which some people find even more distressing and worse than vomiting.

What causes nausea and vomiting?

There are many different causes for nausea and vomiting, such as:

  • Alcohol excess
  • Allergies
  • Cancer
  • Constipation or bowel obstruction
  • Eating disorders (eg, bulimia)
  • Electrolyte abnormalities
  • Emotional stress (fear
  • Excessive alcohol consumption
  • Food poisoning
  • Gallbladder disease
  • Head injury
  • Heart attack
  • Infection (eg, influenza, norovirus)
  • Intense pain
  • Medicines (such as anticonvulsants, antibiotics, chemotherapeutic agents, opioids, oral contraceptives, and other hormones, theophylline)
  • Medication withdrawal (such as from antidepressants, opioids)
  • Medical conditions, such as appendicitis, hepatitis, heart attack, meningitis
  • Motion (travel) sickness
  • Pregnancy or other hormonal changes
  • Stomach ulcers
  • Surgery.

The underlying mechanisms that result in nausea and vomiting are complex and any disruption in one of four nerve pathways (involving areas such as the inner ear, brain, brain stem, or gastrointestinal system) can ultimately lead to the sensation of nausea.

Children are more likely than adults to vomit, and vomiting is common during viral infections, with a milk allergy, and during illnesses that cause a high fever or coughing.

Every individual has a threshold for nausea, one that changes minute-by-minute depending on their anxiety levels, anticipation, expectation, and adaption to whatever has the potential to make them sick. This explains why some people feel sick and others don’t when exposed to the same nauseating stimulus.

When should you see a doctor for nausea and vomiting?

Most cases of nausea or vomiting resolve within 24 to 48 hours, but you should see a doctor:

  • If the child you are caring for is under six years old with vomiting that has lasted for more than a few hours or occurs with diarrhea or if signs of dehydration are present
  • If the child you are caring for is over six years old with vomiting that has lasted more than a day, if signs of dehydration are present, or their fever is higher than 101°F (38.3°C)
  • If your nausea lasts more than a few days
  • If you are vomiting or have diarrhea for more than 24 hours
  • If you are pregnant with constant nausea
  • If you have had a head injury and you are vomiting
  • If there is blood in the vomit (this may be bright red or look like flakes of coffee)
  • If you also have a stiff neck or a headache
  • If you feel very lethargic or confused
  • If you also have severe abdominal pain or rapid breathing or a fast pulse.

How is nausea and vomiting treated?

Some mild cases of nausea and vomiting are best treated with supportive measures, such as eating bland, dry foods; eating small meals throughout the day rather than three large meals; avoiding hard to digest foods; and drinking small amounts of clear sweetened liquids. Specific treatments may include:

  • Electrolyte solutions
  • Sedating antihistamines
  • Anticholinergics
  • Prokinetics
  • Serotonin (5-HT3) antagonists
  • NK-1 antagonists
  • Steroids
  • Dopamine antagonists
  • Anti-anxiety medications
  • Cannabinoids
  • Digestive aids
  • Ginger
  • Acupuncture, Meditation, or Acupressure bands.