Can Food Allergies Cause Vomiting In Babies?

Vomiting is one of the most common food allergic reaction symptoms in babies. However, your child could be vomiting for another reason, or they could just be spitting up. Today, we’ll cover how to tell whether vomiting is a symptom of a food allergy.

In babies and young children, vomiting is one of the most common symptoms of an allergic reaction. However, your child could be vomiting for another reason or they could just be spitting up as their digestive system is still maturing. Today, we’ll cover how to tell whether vomiting is a symptom of a food allergy, or of something else. Plus, we’ll break down the difference between vomiting and spitting up.

Vomiting and Food Allergies

Along with food allergy hives (red raised bumps), vomiting is one of the most common symptoms of a food allergy reaction in babies and young children. Occasional vomiting is a symptom of a mild allergic reaction, while repeated vomiting can be a symptom of a severe allergic reaction.

Vomiting and hives are the most common symptoms of food allergies in babies. Other common food allergy symptoms are swelling, redness, itchiness, coughing, congestion, stomach pain, and nausea. 

Vomiting and food allergy symptoms with photo of baby

Vomiting is actually a symptom of both of the two main types of food allergies immediate-type food allergies and delayed-type food allergies. It could occur alone or with other symptoms.

Immediate-type food allergies are also known as IgE-mediated food allergies. When someone has this type of food allergy, their immune system produces IgE antibodies that detect the specific proteins from foods they are allergic to.

Whenever the person eats a food they are allergic to, the IgE antibodies react to the food and trigger the release of a chemical called histamine, to over-defend the body against the proteins. This causes the body to develop symptoms of an allergic reaction. 

Immediate-type food allergies cause symptoms like hives, swelling, and vomiting soon after someone eats a food that they are allergic to usually within seconds to minutes of eating that food, and almost always within two hours.

Delayed-type food allergies are also known as non-IgE-mediated food allergies. This type of food allergy is much rarer than immediate-type food allergies.

Delayed-type food allergies also involve an immune system response, but don’t involve IgE antibodies. These food allergies cause GI symptoms, including vomiting, diarrhea, stomach pain and abdominal pain, hours to days after someone eats a food that they are allergic to.

One rare type of delayed food allergy, where vomiting is heavily involved, is FPIES (food protein-induced enterocolitis syndrome). FPIES usually appears in babies. It causes vomiting around 2-4 hours after baby eats the food they’re allergic to, and can also cause diarrhea. The vomiting and diarrhea can sometimes be severe. This can cause baby to become pale, feel floppy and become dehydrated, which requires immediate medical attention. Again, though, FPIES is rare.

Since delayed-type food allergy symptoms sometimes take days to show up, it can sometimes be difficult to trace vomiting back to this type of food allergy.

But if your child starts vomiting immediately after eating a food, and exhibits hives or other food allergy symptoms, their vomiting is likely from an immediate-type food allergy. (For a full breakdown of immediate-type food allergy symptoms, please read our previous article on baby allergic reaction symptoms.)

Food Allergy Vomiting Vs. Other Vomiting

Vomiting is a very common food allergy symptom. Still, though, vomiting can have other causes unrelated to food allergies. Vomiting could be an adverse reaction to a food that is not an allergy, or even happen because of something not related to a food.

You also need to know the difference between vomiting and spitting up before assuming that your child is vomiting due to a food allergy.

Vomiting Vs. Spitting Up

Listing out the differences between vomiting and spitting up with image of baby walking

Spitting up (also called reflux) is common in babies, because babies’ digestive systems are still maturing. During their first few months, around half of all babies spit up.

Spitting up still means baby is healthy – it isn’t a sign that anything is wrong. It happens simply because the sphincter (muscle) at the bottom of the esophagus has trouble staying closed, so it causes the contents of the stomach to flow back into the esophagus.

Spit-up is not a concern when what baby spits up easily flows out of the mouth. It is also not a concern when baby seems content (when baby is a “happy spitter”).

But if baby forcefully expels food, and seems uncomfortable or in distress when they do so, this is vomiting, not spit-up.

Remember that spit-up usually looks like a dribble, while vomit shoots out suddenly and forcefully. Vomiting also brings up more liquid than spit up, and may be yellow or green in color.

Nurse Dani of Intermountain Moms breaks down the difference between vomiting and spit-up, and what to do if you see that baby is vomiting:

Other Possible Causes Of Vomiting

If you’ve determined that baby is vomiting and not just spitting up, keep in mind that these other illnesses and conditions may also be causes of vomiting in babies.

Gastroenteritis (a “stomach bug”)

The most common cause of vomiting in babies and young children is gastroenteritis, commonly known as a stomach bug. This is a bacterial or viral infection that is usually brought on by the rotavirus, and that causes vomiting and diarrhea. Your little one should feel better within a day or two.

Other infections

Your baby could also be vomiting because of a different type of infection, such as an ear infection, a urinary tract infection, or (more rarely) meningitis. If your little one shows signs of one of these infections, like vomiting with a fever, contact your pediatrician.

Gastroesophageal reflux disease (GERD)

GERD is gastroesophageal reflux disease, which is caused by stomach contents flowing back into the esophagus. It is a chronic, lasting problem. As we mentioned above, reflux (frequent spitting up) is common in babies and toddlers under the age of two, and especially babies in their first few months of life. But GERD is a chronic digestive disorder that can damage the esophagus and cause vomiting, as well as cause ongoing feeding and growth problems. Half of all GERD cases are caused by either food allergies or food intolerances.

GERD causes forceful, projectile vomiting where your little one is visibly distressed, in contrast to the “happy spitting up” that is normal for babies. If baby has trouble feeding, with symptoms like projectile vomiting or blood in spit up, stomach pain, dehydration, gagging, respiratory symptoms like coughing and wheezing, they may have GERD. If you think your baby has GERD, contact a doctor.

Food intolerances

Food intolerances are different from food allergies. Food intolerances do not involve the immune system. They can cause GI symptoms, including vomiting, diarrhea, stomach pain, abdominal pain, and gas. Food intolerance symptoms tend to develop hours to days after your child eats a food.

If GI symptoms happen on their own, without symptoms like hives, your child likely has a food intolerance. 

More rarely, they could have a delayed-type food allergy if they only have GI symptoms. But food intolerances are much more common than delayed-type food allergies.

Food intolerances are much more common than delayed-type food allergies.

(Immediate-type food allergies cause other symptoms, like hives, along with vomiting. So, your child doesn't have an immediate-type food allergy if they only have GI symptoms from a food, and the GI symptoms happen after a few hours.)

For more on the differences between food allergies and food intolerances, please read our linked article.

Food poisoning

Food poisoning is an illness caused by eating spoiled food, or food that wasn't properly cooked or refrigerated. It happens when bacteria, viruses, or other germs get into food before someone eats it. Food poisoning can cause vomiting, nausea, and diarrhea. But the symptoms usually start showing up a few hours to several hours after eating a contaminated food – later than food allergy symptoms would emerge. And the symptoms of food poisoning are usually limited to GI symptoms (food poisoning doesn't cause hives).

Food poisoning can also affect multiple people in the family at once, if they eat the contaminated food. And if someone later eats the same type of food that isn't spoiled, and they don't have an intolerance or allergy, they won't develop symptoms like vomiting. 

Other allergies (allergies to something other than foods)

Food allergies and other allergies – such as insect sting allergies and medicine allergies  often have similar symptoms. All types of allergies can cause vomiting. But food allergies are more likely to cause vomiting than other allergies, especially in babies and young children. 


My Baby Is Vomiting – Should I Stop Feeding Allergens?

Many parents wonder when to be concerned about vomiting, especially when they’re introducing allergens to babies (including with Ready. Set. Food!).

If baby starts to vomit seconds to hours after you feed them Ready. Set. Food!, and they develop hives or other food allergy reaction symptoms around the same time, stop feeding Ready. Set. Food! and contact your doctor. This could likely be caused by an immediate-type food allergy.

Rest assured, though, that when food allergy reactions do occur in babies, they tend to be mild. Most babies will not have an allergic reaction when introducing a new food, and the few reactions that do occur tend to be mild or moderate.

This is consistent with findings from research led by Dr. Jonathan Spergel (Head of Allergy at Children’s Hospital of Philadelphia), which shows that infants are the age group least likely to experience a severe allergic reaction. In addition, in 3 landmark clinical allergen introduction trials with over 2,000 infant participants, there were zero severe reactions or hospitalizations. Early allergen introduction is safe, and supported by several sets of recent clinical guidelines.

Our Chief Allergist and Board Certified Allergist Katie Marks-Cogan M.D, explains how early allergen introduction is inherently safe:

If you find that baby is vomiting, but this occurs more than two hours after mealtimes, and the only other symptoms they experience are in the GI tract, talk to your doctor. This could be a sign of a delayed-type food allergy, but it is more likely to be from a food intolerance.

Note that repeated, frequent vomiting is always a cause for concern. Although vomiting may not be as frequent from a food allergy reaction in babies, repeated vomiting may be a sign of another condition that needs medical attention.

Call your doctor immediately if:

  • Baby's vomiting lasts for more than a day
  • Baby vomits so much they can't hold down fluids
  • Vomiting appears to cause dehydration (for instance, if baby isn't wetting many diapers, their mouth seems dry, or they cry without tears)
  • Baby has a persistent or high fever along with vomiting
  • You suspect that GERD is causing vomiting

Introduce Allergens Safely and Easily with Ready. Set. Food!

All health-related content on this website is for informational purposes only and does not create a doctor-patient relationship. Always seek the advice of your own pediatrician in connection with any questions regarding your baby’s health.

These statements have not been evaluated by the Food and Drug Administration. Products are not intended to diagnose, treat, cure or prevent any disease.  If your infant has severe eczema, check with your infant’s healthcare provider before feeding foods containing ground peanuts.