Vomiting and Diarrhea

This proceeding discussion of vomiting and diarrhea will be based on infectious causes.  Vomiting and diarrhea due to other causes may not pertain to this handout.

What types of infections can cause vomiting and diarrhea?  The most common causes of acute (sudden or new onset) vomiting and diarrhea are viruses.  Bacterial infections or their toxins also can cause acute vomiting and diarrhea.  Parasites may cause prolonged courses of diarrhea (>10 days).

What is the most important thing to be concerned about with vomiting or diarrhea?  The most important thing to be concerned about is dehydration.  Fluid is being lost either through vomiting and/or diarrhea.  The child may become dehydrated if the child cannot replenish these losses, as well as maintain the usual daily intake of fluids.  Signs of dehydration include:

  1. Crying without tears in infants and young children
  2. Dry mouth
  3. Cracked dry lips
  4. Poor salivation
  5. Sunken eyes
  6. Severely depressed anterior fontanelle (front “soft spot” on head) in infants when sat upright
  7. Not making urine at least once every 8 hours (moderate to severe dehydration)
  8. Doughy skin (severe dehydration)
  9. Poor skin turgor (severe dehydration)—when pulling on the skin, the skin normally “snaps” back if there is an adequate hydration status.  When the patient is severely dehydrated, the skin will stay “tented” when pulled.
  10. Poor capillary refill (severe dehydration)—when pressing on the nails of fingers or toes (or the heel of babies), the nail bed or skin will blanche.  Upon releasing the pressure, the skin should “pink up” in less than 2 seconds.  If the patient is severely dehydrated, then the “pinking up” would take more than 2 seconds, suggesting the patient may be in shock.
  11. Increasing somnolence with other signs of dehydration may suggest shock from severe dehydration.
  12. Greater than 10% weight loss during episodes of vomiting/diarrhea suggest severe dehydration.


If you believe that your child has any signs of dehydration, immediately bring the child to the emergency room for an evaluation.  He/she may need intravenous fluids for rehydration.

How long does vomiting usually last?  Vomiting usually resolves within 72 hours from the initial onset.

How long does diarrhea usually last?  It depends on the cause, but most acute infectious diarrhea lasts 10-14 days.  Diarrhea tends to get better (developing more formed stools) after day #5 of illness.

What medicines may I use for vomiting and diarrhea?  In most cases of vomiting and diarrhea, no medication is needed.  Usually, vomiting and diarrhea usually resolve on their own (self-limiting).

  1. Antibiotic treatment for bacterial causes is usually NOT necessary, unless the cause is either from Shigella sonnei or Salmonella typhi.  Even most causes of bacterial diarrhea are self limiting.  Other indication for antibiotic treatment is if the patient becomes toxic (severely ill appearing, as determined by healthcare professional) or if the blood culture becomes positive for bacterial growth.
  2. Antiemetics (vomiting/nausea preventing medications) may be used for vomiting.  Indications for antiemetics:
    1. To help hold down liquids to prevent dehydration.
    2. Vomit turning bloody—concerns about severe retching causing tears in the esophagus (Mallory-Weiss tears).
    3. Neurologically impaired child with poor gag or cough reflex (inability to protect the airway)—concerns about aspiration (vomiting stomach contents into the lungs).
  3. Antidiarrhea medications—not recommended for infectious diarrhea.  The intestines have natural “drainage” to the outside, thus naturally draining the infection out of the body.  Antidiarrhea medications may make the patient more sick overall by increasing content time of infectious agents in the gut.  For example, if the patient has a bacterial cause for the diarrhea, then the bacteria stays in the gut longer, increasing the chance that the bacteria may invade through the gut wall and into the bloodstream.  Therefore, antidiarrhea medications may make a local infection into a systemic one.
  4. Antiparasitic medication—all parasitic causes of vomiting/diarrhea should be treated with the appropriate antiparasitic medication.


How do I care for my vomiting child?  Like adults, when sick, children and infants don’t want to have “too much” content at once in their stomach, otherwise they will become nauseous and may vomit.

  1. Provide plenty of fluids to maintain adequate hydration.  If vomiting occurs when giving fluids, then give less amount (even just sips, if necessary), but more frequently.  Sometimes, if vomiting is severe, you may have to give your child sips of fluid every 10 to 15 minutes when your child is awake just to keep fluids down.
  2. Avoid irritating fluids (citrus juices, e.g., orange juice).
  3. After 6 hours of not vomiting, you may introduce a bland (tasteless), non-fatty, non-spicy meal.  BRAT (Banana, Rice, Apple sauce, Toast) diet is usually good.
  4. If the patient tolerates the first meal of the bland diet, he/she may eat whatever he/she wants in the next meal.
  5. If vomiting occurs at any time during the reintroduction of solid food, then the patient will have to start over with fluids.

How do I care for my child with diarrhea? 

  1. The most important thing is providing plenty of fluids.
  2. Avoid sugary liquids (sweetened fruit juices) because it can make the diarrhea worse.
  3. Avoid milk products until the diarrhea resolves.  Some viral infections, e.g. rotavirus, may cause a temporary lactase deficiency and worsen diarrhea with formula or drinks with lactose.
  4. If the patient still wears diapers, use zinc oxide ointment (not cream) or petroleum jelly to protect the buttocks from skin maceration.

What kinds of fluids may I use to maintain hydration?  You may use almost any kinds of fluids.  Avoid using plain water, because water doesn’t replenish most of the electrolytes (e.g., sodium, potassium, bicarbonates) and water doesn’t provide carbohydrates for energy.  Here are some rehydration solutions:

  1. Commercial rehydration solutions (e.g., Pedialyte and Enfalyte) replenish some of the electrolytes loss from vomiting and diarrhea and provide carbohydrates for energy.  These commercial rehydration solutions are not very tasty, and toddlers and infants may not like them.  You may mix ¼ fruit juice and ¾ rehydration solution to provide some flavor to the rehydration solution.
  2. Diluted fruit juices can replenish some of the electrolytes loss and provide carbohydrate for energy.  Remember, sweetened fruit juices can make diarrhea worse because of their high sugar content, so don’t forget to dilute them.
  3. Sport drinks replenish some electrolytes and provide carbohydrates.  Depending on the sugar content, you may need to dilute them with water to prevent exacerbating the diarrhea.


When should I bring my child to see a healthcare professional?
Please take your child to the emergency room for intravenous fluids if you suspect that your child is dehydrated or if there is abundant amount of bloody stools/vomitus (blood is “pouring out”).  Otherwise, you can make an appointment with your healthcare professional if:

  1. Vomiting or diarrhea occurs when less than 3 months old.
  2. Mild bloody stools
  3. Mild diarrhea lasting 2 weeks
  4. Fever lasting more than 3 days
  5. Diarrhea with pus

If you have further concerns regarding your child during vomiting or diarrhea episodes, then please consult your healthcare professional.

1-2-3 Pediatrics
3925 75th Street, Suite 105; Aurora, IL 60504
(630) 978-7337