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Vomiting in Infants and Children


Deborah M. Consolini

, MD, Thomas Jefferson University Hospital

Reviewed/Revised Nov 2022
Topic Resources

Vomiting is the uncomfortable, involuntary, forceful throwing up of food. In infants, vomiting must be distinguished from spitting up. Infants often spit up small amounts while being fed or shortly afterward—typically while being burped. Spitting up may occur because infants feed rapidly, swallow air, or are overfed, but it may occur for no apparent reason. Vomiting is typically caused by a disorder. Experienced parents can usually tell the difference between spitting up and vomiting, but first-time parents may need to talk to a doctor or nurse.

Vomiting can cause significant loss of body fluid (dehydration Dehydration in Children Dehydration is loss of water from the body, usually caused by vomiting and/or diarrhea. Dehydration occurs when there is significant loss of body water and, to varying amounts, electrolytes... read more ). Sometimes children cannot drink enough to make up for lost fluid—either because they are continuing to vomit or because they do not want to drink. Children who are vomiting usually do not want to eat, but this lack of appetite rarely causes a problem.

Causes of Vomiting in Infants and Children

Vomiting can be beneficial by getting rid of toxic substances that have been swallowed. However, vomiting is most often caused by a disorder. Usually, the disorder is relatively harmless, but occasionally vomiting is a sign of a serious problem, such as a blockage in the stomach or intestine or increased pressure within the skull (intracranial hypertension).

Common causes

Less common causes

In newborns and infants, some causes, although less common, are important because they may be life threatening:

In older children and adolescents, rare causes include serious infections (such as a kidney infection Kidney Infection Pyelonephritis is a bacterial infection of one or both kidneys. Infection can spread up the urinary tract to the kidneys, or uncommonly the kidneys may become infected through bacteria in the... read more or meningitis Meningitis in Children Bacterial meningitis is a serious infection of the layers of tissue covering the brain and spinal cord ( meninges). Bacterial meningitis in older infants and children usually results from bacteria... read more ), acute appendicitis Appendicitis in Children Appendicitis is inflammation and infection of the appendix (a thin tube of tissue that is connected to the intestines). Appendicitis seems to develop when the appendix becomes blocked either... read more Appendicitis in Children , or a disorder that increases pressure within the skull (such as a brain tumor Overview of Brain and Spinal Cord Tumors in Children The central nervous system is made up of the brain and spinal cord. Central nervous system tumors are the second most common cancer in children under 15 years of age (after leukemia) and the... read more or a serious head injury Severe head injury Head injuries that involve the brain are particularly concerning. Common causes of head injuries include falls, motor vehicle crashes, assaults, and mishaps during sports and recreational activities... read more ). In adolescents, causes also include gastroesophageal reflux disease or peptic ulcer disease Peptic Ulcer in Children A peptic ulcer is a round or oval sore in the lining of the stomach or duodenum where it has been eroded by stomach acid and digestive enzymes. Sores form in the lining of the stomach or duodenum... read more , food allergies Food Allergy A food allergy is an allergic reaction to a particular food. Food allergies are commonly triggered by certain nuts, peanuts, shellfish, fish, milk, eggs, wheat, and soybeans. Symptoms vary by... read more , cyclic vomiting Less common causes Nausea is an unpleasant feeling of needing to vomit. People also may feel dizziness, vague discomfort in the abdomen, and an unwillingness to eat. Vomiting is a forceful contraction of the stomach... read more , a slowly emptying stomach (gastroparesis), pregnancy Contraception and Adolescent Pregnancy Many adolescents engage in sexual activity but may not be fully informed about contraception, pregnancy, and sexually transmitted infections, including hepatitis C and human immunodeficiency... read more , eating disorders Overview of Eating Disorders Eating disorders involve a disturbance of eating or of behavior related to eating, typically including Changes in what or how much people eat Measures people take to prevent food from being... read more , ingestion of a toxic substance Overview of Poisoning Poisoning is the harmful effect that occurs when a toxic substance is swallowed, is inhaled, or comes in contact with the skin, eyes, or mucous membranes, such as those of the mouth or nose... read more (such as large amounts of acetaminophen Acetaminophen Poisoning Acetaminophen, a common ingredient in many prescription and non-prescription drugs, is safe in normal doses, but severe overdose can cause liver failure and death. People sometimes ingest too... read more , iron Iron Poisoning Iron is a mineral essential to life, but taking too much iron can cause severe symptoms, liver damage, and even death. Symptoms develop in stages and begin with vomiting, diarrhea, and abdominal... read more , or alcohol), and frequent use of cannabis (marijuana).

Evaluation of Vomiting in Infants and Children

For doctors, the first goal is to determine whether children are dehydrated and whether the vomiting is caused by a life-threatening disorder.

Warning signs

The following symptoms and characteristics are cause for concern:

  • Lethargy and listlessness

  • In infants, inconsolability or irritability and bulging of the soft spots (fontanelles) between the skull bones

  • In older children, a severe headache, stiff neck that makes lowering the chin to the chest difficult, sensitivity to light, and fever

  • Abdominal pain, swelling, or both

  • Persistent vomiting in infants who have not been growing or developing as expected

  • Bloody stools

  • Bright green or bloody vomit

When to see a doctor

Children with warning signs should be immediately evaluated by a doctor, as should all newborns; children whose vomit is bloody, resembles coffee grounds, or is bright green; and children with a recent (within a week) head injury. If children appear uncomfortable even when not vomiting and their discomfort lasts more than a few hours, they should probably be evaluated by a doctor.

For other children, signs of dehydration, particularly decreased urination, and the amount they are drinking help determine how quickly they need to be seen. The urgency varies somewhat by age because infants and young children can become dehydrated more quickly than older children. Generally, infants and young children who have not urinated for more than 8 hours or who have been unwilling to drink for more than 8 hours should be seen by a doctor.

The doctor should be called if children have more than 6 to 8 episodes of vomiting, if the vomiting continues more than 24 to 48 hours, or if other symptoms (such as cough, fever, or rash) are present.

Children who have had only a few episodes of vomiting (with or without diarrhea), who are drinking at least some fluids, and who otherwise do not appear very ill rarely require a doctor’s visit.

What the doctor does

Doctors first ask questions about the child's symptoms and medical history. Doctors then do a physical examination. A description of the child's symptoms and a thorough examination usually enable doctors to identify the cause of vomiting (see table ).

Doctors ask

  • When the vomiting started

  • How often it occurs

  • What the vomit looks like (including its color)

  • Whether it is forceful (projectile)

  • How much is vomited

Determining whether there is a pattern—occurring at certain times of the day or after eating certain foods—can help doctors identify possible causes. Information about other symptoms (such as fever and abdominal pain), bowel movements (frequency and consistency), and urination can also help doctors identify a cause.

Doctors also ask about recent travel, injuries, and, for sexually active adolescent girls, use of birth control.

A physical examination is done to check for clues to possible causes. Doctors note whether children are growing and developing as expected.



Doctors choose tests based on suspected causes suggested by results of the examination. Most children do not require testing. However, if abnormalities in the abdomen are suspected, imaging tests are typically done. If a hereditary metabolic disorder is suspected, blood tests specific for that disorder are done.

If dehydration is suspected, blood tests to measure electrolytes (minerals necessary to maintain fluid balance in the body) are sometimes done.

Treatment of Vomiting in Infants and Children

If a specific disorder is the cause, it is treated. Vomiting caused by gastroenteritis usually stops on its own.


Making sure children are well-hydrated is important. Fluids are usually given by mouth (see Dehydration in Children Dehydration in Children Dehydration is loss of water from the body, usually caused by vomiting and/or diarrhea. Dehydration occurs when there is significant loss of body water and, to varying amounts, electrolytes... read more ). Oral rehydration solutions that contain the right balance of electrolytes are used. In the United States, these solutions are widely available without a prescription from most pharmacies and from supermarkets. Sports drinks, sodas, juices, and similar drinks have too little sodium and too much carbohydrate and should not be used.

Even children who are vomiting frequently may tolerate small amounts of solution that are given often. Typically, 1 teaspoon (5 milliliters) is given every 5 minutes. If children keep this amount down, the amount is gradually increased. With patience and encouragement, most children can take enough fluid by mouth to avoid the need for fluids by vein (intravenous fluids). However, children with severe dehydration and those who do not take enough fluid by mouth may need intravenous fluids.

Drugs to reduce vomiting

Drugs frequently used in adults to reduce nausea and vomiting are less often used in children because their usefulness has not been proved. Also, these drugs may have side effects that include drowsiness, dizziness, headache, and constipation. However, if nausea or vomiting is severe or does not go away, doctors may give promethazine, prochlorperazine, metoclopramide, or ondansetron to children who are over 2 years of age.


As soon as children have received enough fluid and are not vomiting, they should be given an age-appropriate diet. Infants may be given breast milk or formula.

Key Points

  • Usually, vomiting is caused by gastroenteritis due to a virus and causes no long-lasting or serious problems.

  • Sometimes, vomiting is a sign of a serious disorder.

  • If diarrhea accompanies vomiting, the cause is probably gastroenteritis.

  • Children should be evaluated by a doctor immediately if vomiting persists or they have any warning signs (such as lethargy, irritability, a severe headache, abdominal pain or swelling, vomit that is bloody or bright green, or bloody stools).

Drugs Mentioned In This Article

Generic Name Select Brand Names
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
Anergan-50, Pentazine , Phenadoz , Phenergan, Phenergan Fortis, Prometh Plain, Promethegan
Compazine, Compazine Rectal, Compazine Solution, Compazine Syrup, Compro
Gimoti, Metozolv, Reglan
Zofran, Zofran in Dextrose, Zofran ODT, Zofran Solution, Zuplenz
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