There are several reasons why your baby might be vomiting after a formula feeding, but it’s important to remember that it can be — and often is — very normal.
It’s common for babies to throw up sometimes after feeding on formula or breast milk. Their shiny new digestive systems are still learning what to do with all the yummy milk coming down into their tummy.
However, if your baby often has a hard time keeping their formula down on a regular and frequent basis, let your pediatrician know.
Having a baby around means getting used to soft mushy stuff coming out fairly often. This includes spit-up and vomit.
Spit-up and vomit might seem pretty much the same — and require similar amounts of cleaning to get them off of your sweater and the sofa — but they’re very different. Spitting up is an easy, gentle dribble of milk. Baby may even smile at you as the curd-like spit-up flows from their mouth.
Spit-up is normal in healthy babies, especially if they’re under the age of 1.
On the other hand, vomit takes more effort, as it comes from deeper in your little one’s stomach. It’s a sign that your baby’s stomach is saying nope, not now, please. You might see your baby strain and recoil just before they projectile vomit. This force happens because vomit is squeezed out by the stomach muscles.
Your baby might also look more uncomfortable during and after vomiting. And vomit looks and smells different. This is because it’s usually formula, breast milk, or food (if your baby is eating solids) mixed with stomach juices.
If you’re not sure whether your baby is vomiting or spitting up, look for other vomiting symptoms, like:
- turning red
- arching their back
That said, there doesn’t seem to be agreed-upon definitions of these two terms among healthcare providers, caregivers, and others. Plus, their symptoms may overlap. For example, spitting up may sometimes be forceful, and vomiting may sometimes seem painless.
It’s easier for your baby to overfeed when they’re drinking from a bottle than when they’re breastfeeding. They can also gulp down milk faster from a bottle and rubber nipple. What’s more, because formula is always available, it’s easier for you to give them more milk than they need by accident.
Babies have tiny stomachs. A 4- to 5-week-old infant can only hold about 3 to 4 ounces in their tummy at a time. This is why they need lots of smaller feedings. Drinking too much formula (or breast milk) in one feeding can overfill your baby’s stomach, and it can only come out one way — vomit.
Not burping properly
Some babies need to be burped after every feeding because they swallow lots of air as they gulp down milk. Bottle feeding your baby breast milk or formula may lead to more air-swallowing, as they can gulp even faster.
Too much air in the stomach can make your baby uncomfortable or bloated and trigger vomiting. Burping your baby right after feeding them formula may help prevent this.
To help prevent your baby from swallowing too much air and vomiting after formula feeding, check your baby’s bottle. Make sure you’re using a smaller bottle that’s just big enough to hold a few ounces of milk. Also, check to make sure the nipple hole is not too big, and don’t let your baby continue gulping when the bottle is empty.
Baby or infant reflux
Baby can have acid reflux, indigestion, or occasionally gastroesophageal reflux disease (GERD just like grown-ups! This happens because their stomach and food tubes are still getting used to holding down milk.
Baby reflux happens when milk travels back up toward your baby’s throat and mouth. This usually just causes some painless spitting up, but it can irritate your baby’s throat and trigger gagging and vomiting.
Sometimes, smaller feedings can help prevent baby reflux. If not, don’t worry! Most little ones outgrow baby reflux by the time they’re 1 year old.
While simple constipation would be an uncommon cause of vomiting in an otherwise healthy infant, sometimes baby vomiting happens because of what isn’t happening at the other end.
Most babies who are formula-fed need to poop at least once a day. Anything less than your baby’s typical pattern, though, might indicate they’re constipated.
If your baby is vomiting after a formula feeding, they might be constipated if they have other symptoms, including:
- not pooping for longer than 3–4 days
- a swollen or bloated stomach
- a firm or hard stomach
- crying bouts or irritableness
- straining very hard but not pooping or pooping only a little
- small, hard pellet-like poop
- dry, dark poop
If your baby doesn’t usually vomit after having formula, they might have a stomach bug. Also known as gastroenteritis or the “stomach flu,” a stomach bug is a very common cause of vomiting in babies. Your little one may vomit several times for up to 24 hours.
Other symptoms of a stomach bug include:
- stomach cramps
- stomach rumbling
- diarrhea or watery poop
- mild fever (or none at all in babies)
In rare cases, the cause of your baby’s vomiting might be in the formula. Although it’s uncommon for babies to be allergic to cow’s milk, it may happen to up to 7 percent of babies under the age of 1.
Most children outgrow a milk allergy by the time they’re 5 years old, but it can cause vomiting and other symptoms in babies. A cow’s milk allergy might cause vomiting right after your baby eats. It can also cause vomiting and other symptoms hours or rarely days later.
If your baby has an allergy to milk or something else, they might have other symptoms of an allergic reaction, like:
- skin rash (eczema)
- difficulty breathing
An allergy to milk is different than being lactose intolerant. Lactose intolerance usually causes digestive symptoms like diarrhea. It can also make your baby vomit after drinking formula containing cow’s milk.
Your baby might get temporary lactose intolerance after getting a tummy bug or gastroenteritis, although this is uncommon.
Other symptoms include:
- diarrhea or watery poops
- stomach pain
- stomach rumbling
Note that lactose intolerance is rare in babies under the age of 1.
Some common health conditions can cause vomiting at any time, including after breastfeeding or formula feeding. Some rare genetic conditions can also cause vomiting in babies.
Other causes of vomiting in babies include:
In most cases, minor tweaks can help stop your baby’s vomiting. Remedies to stop your baby’s vomiting after formula depend on what’s causing it. Try some of these tried and tested methods to see what helps your baby:
- feed your baby smaller amounts of formula more often
- feed your baby slowly
- burp your baby after the feeding
- hold your baby’s head and chest up while feeding
- hold your baby upright after a feeding
- make sure your baby doesn’t move around or play too much right after a feeding
- try a smaller bottle and smaller-hole nipple to feed
- check the ingredient list on your baby’s formula
- ask your baby’s doctor if you should try a different kind of formula
- talk to your baby’s doctor about a possible allergic reaction
- dress your baby in looser clothing
- make sure their diaper isn’t on too tightly
If your baby has the stomach flu, you’ll both usually just have to ride it out for a day or two. Most babies and children with a stomach bug don’t need treatment.
If your baby is vomiting, see your doctor or pediatrician right away if they:
- are vomiting often
- are vomiting forcefully
- aren’t gaining weight
- are losing weight
- have a skin rash
- are unusually sleepy or weak
- have blood in their vomit
- have green bile in their vomit
Also, see your doctor urgently if your baby has any sign of dehydration from all the vomiting:
- dry mouth
- crying without shedding tears
- a weak or quiet cry
- floppiness when picked up
- no wet diapers for 8 to 12 hours
It’s pretty common for babies to vomit, especially after feeding. This happens for many reasons, including that these little people are still just getting used to keeping down their milk.
Check with your doctor about what you can do. See your doctor urgently if your baby vomits often for any reason.