Nausea and Vomiting in Infants and Children: A Merck Manual of Patient Symptoms podcast

Nausea is the sensation of impending emesis and is frequently accompanied by autonomic changes, such as increased heart rate and salivation. Nausea and vomiting typically occur in sequence; however, they can occur separately (eg, vomiting can occur without preceding nausea as a result of increased intracranial pressure).

Vomiting is uncomfortable and can cause dehydration because fluid is lost and because the ability to rehydrate by drinking is limited.

Pathophysiology

Vomiting is the final part of a sequence of events coordinated by the emetic center located in the medulla. The emetic center can be activated by afferent neural pathways from digestive (eg, pharynx, stomach, small bowel) and nondigestive (eg, heart, testes) organs, the chemoreceptor trigger zone located in the area postrema on the floor of the 4th ventricle (containing dopamineSome Trade Names
INTROPIN
Click for Drug Monograph
and serotonin receptors), and other CNS centers (eg, brain stem, vestibular system).

Etiology

The causes of vomiting vary with age and range from relatively benign to potentially life threatening (see Table 22: Approach to the Care of Normal Infants and Children: Some Causes of Vomiting in Infants, Children, and Adolescents). Vomiting is a protective mechanism that provides a means to expel potential toxins; however, it can also indicate serious disease (eg, intestinal obstruction). Bilious vomiting indicates a high intestinal obstruction and, especially in an infant, requires immediate evaluation.

Infants: Infants normally spit up small amounts (usually < 5 to 10 mL) during or soon after feedings, often when being burped. Rapid feeding, air swallowing, and overfeeding may be causes, although spitting up occurs even without these factors. Occasional vomiting may also be normal, but repeated vomiting is abnormal.

The most common causes of vomiting in infants and neonates include the following:

• Acute viral gastroenteritis
• Gastroesophageal reflux disease

Other important causes in infants and neonates include the following:

• Pyloric stenosis
• Intestinal obstruction (eg, meconium ileus, volvulus, intestinal atresia, stenosis)
• Intussusception (should be considered in an infant ≥ 3 mo)

Less common causes of recurrent vomiting include sepsis and food intolerance. Metabolic disorders (eg, urea cycle disorders, organic acidemias) are uncommon but can manifest with vomiting.

Older children: The most common cause is

• Acute viral gastroenteritis

Non-GI infections may cause a few episodes of vomiting. Other causes to consider include serious infection (eg, meningitis, pyelonephritis), acute abdomen (eg, appendicitis), increased intracranial pressure secondary to a space-occupying lesion (eg, caused by trauma or tumor), and cyclic vomiting.

In adolescents, causes of vomiting also include pregnancy, eating disorders, and toxic ingestions.

Table 22
PrintOpen table in new window
Some Causes of Vomiting in Infants, Children, and Adolescents Cause* Suggestive Findings Diagnostic Approach Vomiting in infants Gastroenteritis Usually with diarrhea Sometimes fever, contact with a person who has similar symptoms, or both Clinical evaluation Sometimes stool for WBC, culture Gastroesophageal reflux disease Recurrent fussiness after feedings, spitting up, arching of back, poor weight gain Empiric trial of acid suppression Sometimes esophageal pH monitoring study or endoscopy Pyloric stenosis Recurrent projectile vomiting immediately after feeding in neonates aged 3–6 wk (typically first-born males) Emaciated and dehydrated in appearance, sometimes palpable “olive” in right upper quadrant, decreased stools Ultrasonography of pylorus Upper GI contrast study if ultrasonography is unavailable or uncertain Congenital atresias or stenoses Abdominal distention, bilious emesis in first 24–48 h of life (with lesser degrees of stenosis, vomiting can be delayed), polyhydramnios during pregnancy, Down syndrome, jaundice Abdominal x-ray Upper GI series or contrast enema depending on findings Intussusception Colicky progressive abdominal pain, inconsolable crying, drawing of legs up to chest Later, increasing lethargy, bloody stool Typically age 3–36 mo, but can be outside this range Abdominal ultrasonography If ultrasonography is positive or nondiagnostic, air enema (or in some centers, contrast enema) unless patient has signs of peritonitis or perforation Hirschsprung's disease In neonates, delayed passage of meconium, abdominal distention, bilious emesis Abdominal x-ray Contrast enema Rectal biopsy Malrotation In neonates, bilious emesis, abdominal distention and pain, bloody stool Abdominal x-ray Upper GI series with contrast under fluoroscopy Sepsis Fever, lethargy, tachycardia, tachypnea, widening pulse pressure CBC; blood, urine, and CSF cultures Chest x-ray if pulmonary symptoms Food intolerance Abdominal pain, diarrhea, possibly eczematous rashes or urticaria Elimination diet Metabolic disorders Poor feeding, failure to thrive, hepatosplenomegaly, jaundice, cardiomyopathy, dysmorphic features, developmental delay, unusual odors Electrolytes, ammonia, liver function tests, BUN, creatinine, serum glucose, total and direct bilirubin, CBC, PT/PTT Further specific tests based on findings Vomiting in children and adolescents Gastroenteritis Usually with diarrhea Sometimes fever, contact with a person who has similar symptoms, travel Clinical evaluation Sometimes stool for WBC, culture Non-GI infection Fever, often localizing findings (eg, headache, ear pain, sore throat, cervical adenopathy, dysuria, flank pain, chronic nasal discharge) depending on cause Clinical evaluation Testing as needed for suspected cause Appendicitis Initial general malaise and periumbilical discomfort, pain localizing to right lower quadrant, vomiting after pain manifestation, anorexia, fever, tenderness at McBurney's point, decreased bowel sounds Ultrasonography (preferred over CT to limit radiation exposure) Serious infection Fever, toxic appearance, back pain, dysuria (pyelonephritis) Nuchal rigidity, photophobia (meningitis) Listlessness, hypotension, tachycardia (sepsis) CBC, blood culture, urine and CSF cultures, Gram stain Chest x-ray if pulmonary symptoms are present Cyclic vomiting At least 3 self-limited episodes of vomiting lasting 12 h, 7 days between episodes, no organic cause of vomiting Diagnosis of exclusion Intracranial hypertension (caused by tumor or trauma) Nocturnal wakening, progressive recurrent headache made worse by coughing or Valsalva maneuver, nuchal rigidity, visual changes, weight loss, photophobia Brain CT (without contrast) Eating disorders Binge and purge cycles, enamel erosion on teeth, skin lesions on hand from inducing vomiting (Russell's sign) Clinical evaluation Pregnancy Amenorrhea, morning sickness, bloating, breast tenderness, history of sexual activity†, questionable use of contraception Urine pregnancy test Toxic ingestions (eg, acetaminophenSome Trade Names GENAPAP TYLENOL VALORIN Click for Drug Monograph , iron, ethanol) Findings possibly varying by substance Often a history of ingestion Qualitative and sometimes quantitative levels (depending on substance) *Causes are listed in order of frequency. †However, many teens do not admit to sexual activity. Some Causes of Vomiting in Infants, Children, and Adolescents Cause* Suggestive Findings Diagnostic Approach Vomiting in infants Gastroenteritis Usually with diarrhea Sometimes fever, contact with a person who has similar symptoms, or both Clinical evaluation Sometimes stool for WBC, culture Gastroesophageal reflux disease Recurrent fussiness after feedings, spitting up, arching of back, poor weight gain Empiric trial of acid suppression Sometimes esophageal pH monitoring study or endoscopy Pyloric stenosis Recurrent projectile vomiting immediately after feeding in neonates aged 3–6 wk (typically first-born males) Emaciated and dehydrated in appearance, sometimes palpable “olive” in right upper quadrant, decreased stools Ultrasonography of pylorus Upper GI contrast study if ultrasonography is unavailable or uncertain Congenital atresias or stenoses Abdominal distention, bilious emesis in first 24–48 h of life (with lesser degrees of stenosis, vomiting can be delayed), polyhydramnios during pregnancy, Down syndrome, jaundice Abdominal x-ray Upper GI series or contrast enema depending on findings Intussusception Colicky progressive abdominal pain, inconsolable crying, drawing of legs up to chest Later, increasing lethargy, bloody stool Typically age 3–36 mo, but can be outside this range Abdominal ultrasonography If ultrasonography is positive or nondiagnostic, air enema (or in some centers, contrast enema) unless patient has signs of peritonitis or perforation Hirschsprung's disease In neonates, delayed passage of meconium, abdominal distention, bilious emesis Abdominal x-ray Contrast enema Rectal biopsy Malrotation In neonates, bilious emesis, abdominal distention and pain, bloody stool Abdominal x-ray Upper GI series with contrast under fluoroscopy Sepsis Fever, lethargy, tachycardia, tachypnea, widening pulse pressure CBC; blood, urine, and CSF cultures Chest x-ray if pulmonary symptoms Food intolerance Abdominal pain, diarrhea, possibly eczematous rashes or urticaria Elimination diet Metabolic disorders Poor feeding, failure to thrive, hepatosplenomegaly, jaundice, cardiomyopathy, dysmorphic features, developmental delay, unusual odors Electrolytes, ammonia, liver function tests, BUN, creatinine, serum glucose, total and direct bilirubin, CBC, PT/PTT Further specific tests based on findings Vomiting in children and adolescents Gastroenteritis Usually with diarrhea Sometimes fever, contact with a person who has similar symptoms, travel Clinical evaluation Sometimes stool for WBC, culture Non-GI infection Fever, often localizing findings (eg, headache, ear pain, sore throat, cervical adenopathy, dysuria, flank pain, chronic nasal discharge) depending on cause Clinical evaluation Testing as needed for suspected cause Appendicitis Initial general malaise and periumbilical discomfort, pain localizing to right lower quadrant, vomiting after pain manifestation, anorexia, fever, tenderness at McBurney's point, decreased bowel sounds Ultrasonography (preferred over CT to limit radiation exposure) Serious infection Fever, toxic appearance, back pain, dysuria (pyelonephritis) Nuchal rigidity, photophobia (meningitis) Listlessness, hypotension, tachycardia (sepsis) CBC, blood culture, urine and CSF cultures, Gram stain Chest x-ray if pulmonary symptoms are present Cyclic vomiting At least 3 self-limited episodes of vomiting lasting 12 h, 7 days between episodes, no organic cause of vomiting Diagnosis of exclusion Intracranial hypertension (caused by tumor or trauma) Nocturnal wakening, progressive recurrent headache made worse by coughing or Valsalva maneuver, nuchal rigidity, visual changes, weight loss, photophobia Brain CT (without contrast) Eating disorders Binge and purge cycles, enamel erosion on teeth, skin lesions on hand from inducing vomiting (Russell's sign) Clinical evaluation Pregnancy Amenorrhea, morning sickness, bloating, breast tenderness, history of sexual activity†, questionable use of contraception Urine pregnancy test Toxic ingestions (eg, acetaminophenSome Trade Names GENAPAP TYLENOL VALORIN Click for Drug Monograph , iron, ethanol) Findings possibly varying by substance Often a history of ingestion Qualitative and sometimes quantitative levels (depending on substance) *Causes are listed in order of frequency. †However, many teens do not admit to sexual activity.

Evaluation

Evaluation includes assessment of severity (eg, presence of dehydration, surgical or other life-threatening disorder) and diagnosis of cause.

History: History of present illness should determine when vomiting episodes started, frequency, and character of episodes (particularly whether vomiting is projectile, bilious, or small in amount and more consistent with spitting up). Any pattern to the vomiting (eg, after feeding, only with certain foods, primarily in the morning or in recurrent cyclic episodes) should be established. Important associated symptoms include diarrhea (with or without blood), fever, anorexia, and abdominal pain, distention, or both. Stool frequency and consistency and urinary output should be noted.

Review of systems should seek symptoms of causative disorders, including weakness, poor suck, and failure to thrive (metabolic disorders); delay in passage of meconium, abdominal distention, and lethargy (intestinal obstruction); headache, nuchal rigidity, and vision change (intracranial disorders); food bingeing or signs of distorted body image (eating disorders); missed periods and breast swelling (pregnancy); rashes (eczematous suggests food intolerance, petechial suggests CNS infection, urticarial suggests food allergy); ear pain and sore throat (focal non-GI infection); and fever with headache, back pain, or abdominal pain (meningitis, pyelonephritis, or appendicitis).

Past medical history should note history of travel (possible infectious gastroenteritis), any recent head trauma, and unprotected sex (pregnancy).

Physical examination: Vital signs are reviewed for indicators of infection (eg, fever) and volume depletion (eg, tachycardia, hypotension).

During the general examination, signs of distress (eg, lethargy, irritability, inconsolable crying) and signs of weight loss (cachexia) or gain are noted.

Because the abdominal examination may cause discomfort, the physical examination should begin with the head. The head and neck examination should focus on signs of infection (eg, red, bulging tympanic membrane; bulging anterior fontanelle; erythematous tonsils) and dehydration (eg, dry mucous membranes, lack of tears). The neck should be passively flexed to detect resistance or discomfort, suggesting meningeal irritation.

Cardiac examination should note presence of tachycardia (eg, dehydration, fever, distress). Abdominal examination should note distention; presence and quality of bowel sounds (eg, high-pitched, normal, absent); tenderness and any associated guarding, rigidity, or rebound (peritoneal signs); and presence of organomegaly or mass.

The skin and extremities are examined for petechiae or purpura (severe infection) or other rashes (possible viral infection or signs of atopy), jaundice (possible metabolic disorder), and signs of dehydration (eg, poor skin turgor, delayed capillary refill).

Growth parameters and signs of developmental progress should be noted.

Red flags: The following findings are of particular concern:

• Lethargy and listlessness
• Inconsolability and bulging fontanelle in infant
• Nuchal rigidity, photophobia, and fever in older child
• Peritoneal signs or abdominal distention (“surgical” abdomen)
• Persistent vomiting with poor growth or development

Interpretation of findings: Initial findings help determine severity of diagnosis and need for immediate intervention.

• Any neonate or infant with recurrent or bilious (yellow or green) emesis or projectile vomiting most likely has a GI obstruction and probably requires surgical intervention.
• An infant or young child with colicky abdominal pain, signs of intermittent pain or listlessness, and absent or bloody stools needs to be evaluated for an intussusception.
• A child or adolescent with fever, nuchal rigidity, and photophobia should be evaluated for meningitis.
• A child or adolescent with fever and abdominal pain followed by vomiting, anorexia, and decreased bowel sounds should be evaluated for appendicitis.
• Recent history of head trauma or progressive headaches and visual changes indicate intracranial hypertension.

Other findings can be interpreted primarily depending on age (see Table 22: Approach to the Care of Normal Infants and Children: Some Causes of Vomiting in Infants, Children, and Adolescents).

In infants, irritability, choking, and respiratory signs (eg, stridor) may be manifestations of gastroesophageal reflux. A history of poor development or neurologic manifestations suggests a CNS or metabolic disorder. Delayed passage of meconium, later onset of vomiting, or both may indicate Hirschsprung's disease or an intestinal stenosis.

In children and adolescents, fever suggests infection; the combination of vomiting and diarrhea suggests acute gastroenteritis. Lesions on fingers and erosion of tooth enamel or an adolescent unconcerned about weight loss suggests an eating disorder. Morning nausea and vomiting, amenorrhea, and possibly weight gain suggest pregnancy. Vomiting that has occurred in the past and is episodic, short-lived, and has no other accompanying symptoms suggests cyclic vomiting.

Testing: Testing should be directed by suspected causative disorders (see Table 22: Approach to the Care of Normal Infants and Children: Some Causes of Vomiting in Infants, Children, and Adolescents). Imaging studies are typically done to evaluate abdominal pathology. Various specific blood tests are done to diagnose inherited metabolic disorders.

If dehydration is suspected, serum electrolytes should be measured.

Treatment

Treatment is targeted at the causative disorder. Drugs frequently used in adults to decrease nausea and vomiting are rarely used in children because the usefulness of treatment has not been proved and because they have potential risks of adverse effects and of masking an underlying condition.

Rehydration is important (see Dehydration and Fluid Therapy in Children: Oral Rehydration).

Key Points

• In general, the most common cause of vomiting is acute viral gastroenteritis.
• Not all vomiting is caused by gastroenteritis.
• Diarrhea suggests an infectious GI cause.
• Bloody stools or lack of bowel movements suggests an obstructive cause.
• Persistent vomiting (especially in an infant) requires immediate evaluation.

Last full review/revision February 2010 by Eve R. Colson, MD; Rachel L. Chapman, MD; Melissa R. Held, MD

Content last modified February 2012