When your baby vomits, the first thing to do is prop their head up slightly to prevent them from inhaling vomit into their lungs, then hold them upright or on their side. Most infant vomiting is caused by a stomach bug or overfeeding and resolves on its own within 12 to 24 hours. Your main jobs are keeping your baby hydrated, watching for warning signs, and knowing when the situation calls for medical help.
Spit-Up vs. Vomiting
Before anything else, it helps to know whether your baby is actually vomiting or just spitting up. Spit-up is a gentle flow of milk that oozes out of the mouth, usually just one or two mouthfuls after a feeding. It happens because the muscle between the esophagus and stomach is still immature and sometimes relaxes when the stomach is full. Your baby might burp at the same time, but they generally look unbothered.
Vomiting is different. It comes out with force, shooting from the mouth rather than dribbling. Your baby’s abdominal muscles contract to push the contents up. If your baby is spitting up small amounts and is otherwise happy, gaining weight, and feeding well, that’s normal and doesn’t need treatment. True vomiting, especially if it happens more than once or twice, is what the rest of this article addresses.
What to Do Right Away
Prop your baby’s head up slightly and keep them upright or tilted to one side. This reduces the risk of vomit getting into their airway. Don’t lay them flat on their back while they’re actively vomiting. Once the episode passes, gently clean their face and change any soiled clothing so they’re comfortable.
Wait about 15 to 30 minutes before offering any fluids. If you try to feed right away, the stomach is more likely to reject it again. After that short pause, offer small, frequent sips rather than a full feeding. For breastfed babies, nurse for shorter stretches more often. For formula-fed babies, offer half an ounce to an ounce at a time. If your baby keeps that down for 15 to 20 minutes, you can gradually increase the amount.
Keeping Your Baby Hydrated
Dehydration is the biggest practical risk when a baby is vomiting repeatedly. For babies older than a few months, an oral rehydration solution (sold as Pedialyte in most pharmacies) is the best option because it replaces both water and the salts your baby loses. The general guideline for rehydration is 50 to 100 milliliters per kilogram of body weight over four hours, but for home care, the simplest approach is to offer frequent small amounts, about a teaspoon every few minutes, and slowly increase as your baby tolerates it.
Don’t give plain water to young infants. Their kidneys can’t handle it well, and it doesn’t replace lost electrolytes. Avoid juice, soda, and sports drinks too. These are high in sugar, which can actually pull more water into the gut and worsen diarrhea or vomiting. Breast milk is an excellent rehydration fluid for babies who are still nursing, so continue breastfeeding if your baby will take it.
Signs of Dehydration to Watch For
Check your baby’s diapers. Fewer than three wet diapers in 24 hours, or no wet diaper for three hours in a young infant, is a red flag. Dark-colored urine is another sign that fluids are running low.
Other physical signs include:
- Dry mouth and cracked lips
- No tears when crying
- Sunken eyes, cheeks, or the soft spot on top of the skull
- Skin that doesn’t flatten back right away after being gently pinched
- Unusual crankiness or lack of energy
- Rapid heart rate
If you notice several of these together, your baby needs medical evaluation promptly.
When Vomiting Needs Medical Attention
Most vomiting passes without a trip to the doctor. But certain patterns signal something more serious. Call your pediatrician or seek care if your baby:
- Is under 12 weeks old and has vomited two or more times (not counting normal spit-up). Young infants have very little reserve, and any fever combined with vomiting at this age warrants immediate evaluation.
- Has vomited for more than 12 hours without improvement, or for more than 24 hours total.
- Has green or blood-tinged vomit. Green (bile-colored) vomit can indicate a bowel obstruction. Blood in the vomit always needs evaluation.
- Shows signs of dehydration, particularly no urine for more than 8 hours.
- Has a fever above 104°F (40°C), or any fever at all if under 12 weeks old.
- Has severe stomach or back pain between vomiting episodes.
- Is vomiting everything (including breast milk or Pedialyte) for more than 8 hours straight.
Call 911 if your baby cannot be woken up, is not moving, or you feel something is seriously wrong. Trust your instincts on this one.
Common Causes of Infant Vomiting
Gastroenteritis, commonly called a stomach bug, is by far the most frequent cause. It’s usually triggered by a virus, leads to vomiting and sometimes diarrhea, and typically clears within a day or two. Overfeeding can also cause vomiting, especially in bottle-fed babies who take in more than their stomach can handle in one sitting.
A few less common but important causes are worth knowing about. Pyloric stenosis is a condition where the muscle at the stomach’s exit thickens and narrows, blocking food from passing through. It typically shows up between 2 and 7 weeks of age, is more common in boys, and causes forceful, projectile vomiting after feedings. Babies with pyloric stenosis seem hungry all the time because they can’t keep food down. This requires medical treatment, so if your young infant is having increasingly forceful vomiting after every feed, bring it up with your doctor quickly.
Food protein reactions (sometimes called FPIES) can cause intense vomiting a few hours after eating a trigger food, often when solids are being introduced. Other serious but rare causes include intestinal blockages and infections beyond the stomach. These are uncommon, but they’re the reason green or bloody vomit and extreme lethargy always need evaluation.
Getting Back to Normal Feedings
Once your baby has gone a few hours without vomiting, you can start working back toward regular feedings. For breastfed babies, return to your normal nursing schedule but keep sessions a bit shorter at first. For formula-fed babies, start with smaller, more frequent bottles (about half the usual amount) and increase over the next 12 to 24 hours as your baby tolerates it.
If your baby is on solids, stick to bland, easy-to-digest foods for the first day or two after vomiting stops. There’s no need to withhold food for long periods. Babies recover faster when they return to normal nutrition relatively quickly, as long as they’re keeping fluids down first. If vomiting returns when you reintroduce regular feedings, scale back to smaller amounts and try again in an hour or two.