Key Takeaways

Gas in a healthy baby is not a problem to cure. It is air swallowed during feeds plus normal digestion, and healthy babies pass it many times a day.

The lever that works is mechanical: less air swallowed. Feed upright, use a slower flow, let powdered formula settle before serving, and burp mid-feed ¹.

Gas drops do not survive the evidence. A Cochrane review found no support for simethicone, with a response ratio of 0.95 against placebo ².

Probiotics are the one exception, and only for breastfed babies with colic: four trials in 345 infants, with no effect in formula-fed babies ³.

Most “gassy baby” evenings are colic, not gas. That distinction decides whether you are fixing a feeding or riding out a developmental phase ⁴.

The short answer

Almost every baby is gassy, and almost none of them need treatment for it. The word describes two ordinary things: air swallowed during a feed, and gas produced when gut bacteria ferment what was not digested.

Neither is a disease. A healthy baby who farts, strains, grunts, and goes red in the face is doing what the gut does in the first three months, while it learns to coordinate. Gas that comes out is doing its job.

What parents usually want is not less gas but less crying. Those are different goals, and separating them is the most useful thing this page can do. If your baby is happy between episodes and growing well, you are managing a nuisance. If your baby is crying for hours in the evening and cannot be settled, you are probably looking at colic, which is a different problem with a different evidence base ⁴.

The timing is the reassuring part. Colic usually starts when a baby is a few weeks old and stops by 3 to 4 months, and no product has been shown to shorten it ⁴.

What gas actually is

Two sources, and they behave differently.

Swallowed air arrives with every feed. A baby who is feeding fast, lying flat, or working at a bottle with a fast nipple takes in more of it. That air travels through the gut and comes out as a burp or as flatulence. This is the part you can influence.

Fermentation gas is produced when bacteria break down lactose and fiber that reached the colon undigested. You cannot remove it, and you would not want to.

The AAP’s own advice for parents starts with an expectation, not a product: there is “really no need for parents to pay a high price in exchange for less gas,” and any attempt should come “with only modest expectations, since breaking up gas is definitely hard to do” ¹. That sentence is worth more than the rest of this page, because it tells you where to put your effort and where to stop.

What the word hides is a set of conditions that sound like gas and are not. The table below is not a diagnosis tool. It is a list of reasons to stop treating gas and start looking at something else.

What you are seeing	What it usually is
Evening crying that builds and passes, hard to soothe	Colic, not gas ⁴
Bringing up milk, arching, sour breath	Reflux
Blood in the stool, eczema, vomiting, poor weight gain	Possible milk protein allergy ⁵
Straining, hard stools, days between them	Constipation
Fast feeds, large volumes, gulping	Air swallowed with the feed, and sometimes overfeeding

The one lever that works

If you want less gas, reduce how much air goes in. That is the whole mechanism, and every measure below is a version of it.

Feed upright. The NHS recommends sitting or holding a baby upright during feeding to stop them swallowing air, and lists it as a practical measure for a windy, crying baby ⁴.

Slow the flow. A nipple that delivers milk faster than the baby can swallow makes them take air with it. The AAP recommends slowing the flow and trying different nipples and bottles, describing it as trial and error rather than a solved problem ¹.

Let powdered formula settle. Mixing and shaking a bottle puts air bubbles into the liquid, which the baby then swallows. The AAP suggests using ready-to-feed or concentrated formula in the early days, or letting freshly mixed powder stand before serving ¹. This is a five-minute fix that costs nothing.

Burp mid-feed, not only at the end. A baby who takes half a feed, burps, and continues may swallow less accumulated air than one who finishes the whole bottle first.

Keep them upright for a while after. Holding a baby upright for a spell after a feed is an extension of the position the NHS recommends during it, and it costs nothing ⁴.

That is the complete list of things with a plausible mechanism. None of it requires a purchase, and none of it promises a quiet evening.

What does help is knowing which feeds are hardest. If two evening feeds produce most of the gulping, those are the ones to change. The burp tracker records when burps happen and which feeds they follow, which is more reliable than a general impression after a long day. The bottle pacing guide covers the flow side in more detail.

What the remedies aisle claims

The products are where the money and the confidence both live, and where the evidence thins out fastest.

Remedy	What the evidence says	Verdict
Simethicone drops	No difference in crying hours in one small trial; a pooled analysis of two crossover studies found responders at 0.95 against placebo, across 110 infants, on low-quality evidence ²	No support
Herbal and gripe water products	Lower-quality evidence of benefit, with effects varying widely between studies; the reviewers concluded they cannot be recommended ²	Not recommended
Dicyclomine	One usable trial showed a response, and two of five studies reported adverse effects including drowsiness ²	Not for infants
Sucrose	One very low-quality trial ²	No useful evidence
Probiotics	Effective in breastfed infants with colic, no significant effect in formula-fed infants ³	Narrow use

The Cochrane review that produced most of that table pooled 18 trials and 1,014 infants, and its conclusion is blunt: “We found no evidence to support the use of simethicone as a pain-relieving agent for infantile colic” ². It also notes that every included study was small and at high risk of bias, which is the honest reason the whole field looks thin.

The NHS goes further than the trials do. Its colic page says remedies “are available from pharmacies and some shops, but they’re not recommended and there’s no evidence they help colic” ⁴. That is a blanket statement, and the next section is the one place where it is too broad.

The exception: probiotics

One intervention has a trial base that survives scrutiny, and it comes with a condition attached.

An individual-participant meta-analysis pooled four double-blind trials covering 345 infants with colic ³. At day 21, the probiotic group had crying and fussing times that had fallen 25.4 minutes more than placebo, with a 95% confidence interval from -47.3 to -3.5 minutes. Treatment success was 1.7 times as likely.

Then the split that matters. The effect was large in breastfed infants, with a number needed to treat of 2.6. In formula-fed infants it was not significant, and the authors said there were not enough data to conclude either way ³.

So the accurate sentence is narrower than the marketing and broader than the NHS page: for a breastfed baby with colic, Lactobacillus reuteri DSM 17938 has the best evidence of anything in the category. For a formula-fed baby, nobody has shown it works.

The trials used one specific strain at one dose, and supplements on the shelf are not interchangeable. That makes this a conversation with your pediatrician rather than a shopping decision.

Do vented bottles work?

This is the newest evidence in the field, and it is unusually clean.

A 2026 randomized trial enrolled 1,055 infants aged 0 to 90 days across five hospitals in China, and compared bottom-vented bottles with teat-vented bottles over 14 days ⁶. The primary outcome was mild gastrointestinal discomfort at week 2.

It came back null. Discomfort was 35.5% in the bottom-vented group and 37.9% in the teat-vented group, a relative risk of 0.94 with a confidence interval from 0.80 to 1.10 ⁶.

The secondary outcomes were more interesting. Crying during or after feeding was lower with the bottom-vented bottle, 32.2% against 40.8%, a relative risk of 0.79 ⁶. A post hoc subgroup found a larger benefit in babies aged 61 to 90 days, but not in younger ones.

The fair reading is that bottle design changes something real and small. Crying was reported lower, although that was a secondary outcome in a single trial. If you already have a bottle that works, this is not a reason to replace it. If you are choosing, it is a tiebreaker rather than a treatment.

When it isn’t gas

The most expensive mistake in this area is treating a milk protein allergy as gas for two months.

Cow’s milk protein allergy is uncommon but not rare. The AAP puts it at two or three babies out of every hundred who are exclusively breastfed, and it is the most common allergic reaction in that group ⁵. The signs are specific enough to act on: severe colic, abdominal discomfort, eczema or hives, vomiting, diarrhea that often contains blood, or breathing difficulty in the hours after a feed ⁵.

None of those are gas. All of them can present as a baby who seems gassy and unhappy.

Reflux is the second overlap. A baby who brings up milk, arches during feeds, or has sour breath is not swallowing too much air; the valve at the top of the stomach is doing what it does at this age. Our guide to normal spit-up versus vomiting covers where that line sits.

Constipation is the third. Straining is not the same as constipation, and a baby who strains while passing soft stool is not constipated. The poop after starting solids guide covers what stool should look like at each stage.

What to stop doing

Do not switch formulas repeatedly. A change needs time before it can be judged, and a baby on their fourth formula in three weeks has no baseline. If you suspect a milk protein allergy, that is a conversation about a specific type of formula, not a rotation. The formula selection guide covers the categories.

Do not eliminate foods from your diet by default. The AAP is explicit that there is no evidence that avoiding certain foods while breastfeeding prevents allergies, and warns against removing so many foods that the parent is left with too little to eat ⁵. If a specific food reliably causes distress, that is worth noticing. A blanket elimination diet is not.

Do not buy spinal manipulation or cranial osteopathy. The NHS names both, and says there is little evidence they work and they may hurt your baby ⁴.

Do not treat every evening as a gas emergency. If the pattern is hours of crying at the same time each day in an otherwise healthy baby, you are in colic territory, and the useful question is how to survive the window rather than what to add to the bottle. The guide to how much crying is normal has the numbers, and the soothing guide has the techniques.

When to call

Most gas needs no intervention. These situations do.

Go to emergency care or call emergency services for a weak or high-pitched cry, or a cry that does not sound like your baby’s normal cry ⁴. A hard, swollen abdomen, green or bloody vomit, or a baby who is limp or difficult to wake are emergencies for separate reasons and take priority over any question about gas.

Make an appointment if your baby is not growing or putting on weight as expected, if symptoms are still there after 4 months, if there is blood in the stool, or if nothing you try makes any difference ⁴. Also book one if you are the one struggling. The NHS lists “you’re finding it hard to cope” as a reason to call, which is the right framing: persistent infant crying is a household problem, not only a baby problem ⁴.

Frequently asked questions

Is it normal for my baby to pass a lot of gas?

Yes. Swallowed air and fermentation both produce gas, and a healthy baby passes it many times a day. The amount varies between babies and between feeds, and it is not a sign of a digestive problem on its own.

Do gas drops work?

Simethicone, the most common type, has no support from the trials that tested it: a response ratio of 0.95 against placebo across 110 infants ². Herbal products have weak evidence and are not recommended ². The NHS says none of them are recommended ⁴.

Does my diet cause gas in my breastfed baby?

Sometimes, for a specific food, and rarely enough to justify a broad elimination. The AAP advises against removing many foods and notes there is no evidence that avoiding foods prevents allergies ⁵. If a milk protein allergy is suspected, that is a different and more specific conversation.

How long does it last?

The gas itself does not go away, because it is normal. The hard part does. Colic usually starts at a few weeks and stops by 3 to 4 months, and the evening crying tends to fade before the digestion matures ⁴.

Is it gas or colic?

Colic is defined by the crying: more than 3 hours a day, 3 days a week, for at least a week, in an otherwise healthy baby ⁴. Gas is a symptom that comes and goes with feeds. If the crying clusters in the evening and your baby is fine the rest of the day, the useful label is colic.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Gas, crying, and feeding problems overlap, and the studies here describe groups rather than your child. Talk to your pediatrician or health visitor before changing formula, starting a supplement, or cutting foods from your diet. Seek urgent care for a weak or high-pitched cry, a swollen abdomen, green or bloody vomit, or a baby who is hard to wake.

Jana L, Shu J, “Gas Relief for Babies,” HealthyChildren.org (American Academy of Pediatrics), accessed October 2026. Source ↩ ↩² ↩³ ↩⁴
Biagioli E, Tarasco V, Lingua C, Moja L, Savino F, “Pain-relieving agents for infantile colic,” Cochrane Database of Systematic Reviews, September 2016. Source ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸
Sung V, D’Amico F, Cabana MD, et al., “Lactobacillus reuteri to Treat Infant Colic: A Meta-analysis,” Pediatrics, January 2018. Source ↩ ↩² ↩³ ↩⁴
NHS, “Colic,” reviewed 2025. Source ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴
American Academy of Pediatrics, “Infant Allergies and Food Sensitivities,” HealthyChildren.org, accessed October 2026. Source ↩ ↩² ↩³ ↩⁴ ↩⁵
Liu Y, Ding YF, Yu HZ, et al., “Feeding Bottles With Different Venting Methods and Gastrointestinal Discomfort in Infants: A Randomized Clinical Trial,” JAMA Network Open, March 2026. Source ↩ ↩² ↩³