Reflux in babies

8 min read

Babies often bring up milk during or shortly after feeding – this is known as 'possetting', or 'reflux'.

This is different to vomiting, where the baby's muscles forcefully contract (

vomiting in babies
is covered separately). Reflux is just your baby passively "spitting up" whatever they have just swallowed.

However, it can still be upsetting to parents, and it's natural to be worried that something is wrong.

It's important know that reflux is normal, and often just the result of a baby's underdeveloped oesophagus (food canal).

It usually stops when the baby reaches 12-14 months of age, when the ring of muscle at the bottom of their oesophagus fully develops and closes off, preventing stomach contents from leaking out. It's unusual if reflux continues at 18 months.

Only in a small number of cases can reflux be a sign of a more serious problem, such as

gastro-oesophageal reflux disease (GORD)
, a milk allergy or a blockage.

What tips can I try to help my baby's reflux?

It should generally help to:

  • burp your baby regularly throughout feeding
  • avoid overfeeding your baby – don’t force them to take more milk than they want (some babies prefer to feed little and often)
  • check that the hole in your baby’s teat is not too big – giving milk too quickly can cause regurgitation
  • hold your baby upright for a period of time after feeding

Bear in mind that if your baby brings up a lot of milk, they may be hungry again quite quickly.

For more general advice on feeding your baby, you can read our bottle feeding advice and help for breastfeeding problems.

It can also help to raise the head end of your child's cot or crib when they are sleeping – try using books under the legs of the cot or crib, or placing a pillow underneath the mattress at the head end (never put any pillows inside the cot). Your baby should still be laid down to sleep on their back.

When should I see my doctor?

If reflux happens often, or your baby is violently sick, appears to be in pain or you’re worried for any other reason, talk to your health visitor or doctor – especially if they have any of the following symptoms:

  • coughing, gagging or trouble swallowing
  • frequent projectile vomiting
  • persistent crying and being irritable
  • wheezing
  • bad breath
  • difficulty sleeping
  • arching their back during or after a feed
  • drawing their legs up to their tummy after feeding
  • refusing a feed even though they're happy to suck on a dummy or similar
  • not gaining much weight, or losing weight

What might the problem be, in this case?


Babies who repeatedly bring up their food after feeding may have GORD, which is a more serious, long-term form of reflux.

Normally, a ring of muscle at the bottom of the oesophagus acts like a valve, opening to let food fall into the stomach, then closing to prevent acid leaking out of the stomach.

In GORD, this muscle becomes weak or relaxes when it shouldn't, and doesn't close properly. This allows the acidic stomach contents to rise up and irritate the lining of the oesophagus.

GORD is more common in babies who:

  • were born prematurely
  • had a very low birth weight
  • are allergic to cows' milk
  • have a muscle or nerve disorder, such as cerebral palsy

As your baby grows older, the muscle should open only when he or she swallows, and remain tightly closed at all other times to prevent stomach contents escaping. This is why most babies grow out of reflux by 18 months.

An allergy

If you think your baby is having a reaction to infant formula or cows' milk, tell your doctor. Some of the signs are a skin rash, vomiting and diarrhoea.

Your doctor can prescribe special formula feeds called "extensively hydrolysed protein feeds".

If your baby is allergic to cows' milk, eliminating it from their diet for two to three weeks should reduce their vomiting considerably. If you breastfeed, you'll need to exclude cows' milk from your own diet.

Some infant formula is labelled as hypoallergenic, but this is not suitable for babies with a diagnosed cows' milk allergy. Always talk to your doctor before using hypoallergenic or soya-based infant formula, as babies who are allergic to cow's milk may also be allergic to soya.

If your baby continues to vomit despite cutting out cows' milk, it's unlikely that an allergy is the problem.

A blockage

It's rare, but possible, that your baby's reflux may be caused by a blockage in their digestive tract.

Their oesophagus may be blocked or narrowed (known as an "oesophageal stricture"), or there may be a blockage between your baby's stomach and small intestine (known as "pyloric stenosis").

How are these conditions investigated?

If your baby has severe symptoms, your doctor may refer you to a paediatrician for further investigation (a paediatrician is a specialist in treating disorders in children).

Your baby may have one or more of the following tests.

An upper endoscopy

An endoscopy is a procedure where the inside of the body is examined using an endoscope – a long, thin, flexible tube that has a light source and a video camera at one end.

Your baby may need an upper endoscopy (examination of their oesophagus and stomach) if they continue to have problems, despite feeding changes and medication.

The endoscope will be carefully fed through your baby's mouth and down their oesophagus after they've been sedated and given extra oxygen. An instrument on the end of the endoscope can be used to take a biopsy (tissue sample) of the oesophagus. This will be sent to a laboratory and examined to see if there's any inflammation.

Read more about an


Impedance-pH monitoring of the oesophagus

Impedance-pH monitoring measures the amount of liquid and acid in your baby's oesophagus.

It is carried out in hospital, by a paediatrician, as part of an upper endoscopy.

A thin tube will be passed through your baby's nose or mouth to their stomach while they are awake. It is taped to your baby's cheek, where it remains for 24 hours.

The end of the tube has sensors to detect when and how much acid or liquid travels up into your baby's oesophagus. The other end is attached to a monitor outside your baby's body, which shows the measurements taken.

Barium swallow test

A barium swallow test, sometimes called an "upper GI series", can identify blockages or problems with the muscles used during swallowing. It's used to rule out an abnormality with your baby's oesophagus.

Your baby will rest in front of an X-ray machine and drink a barium solution from a bottle. An X-ray will be taken, and the barium will coat the inside of your baby's digestive tract, showing its shape.

What treatments can my doctor offer me?


Treatment for babies and toddlers with mild symptoms of GORD isn't always needed, because they often grow out of the condition after a few months.

In the past, health professionals would recommend adding a thickener (such as cereal) to breast milk or formula feed to make it stickier and heavier – which, in theory, would make it more likely to stay in the baby's stomach. However, there's no scientific evidence to support this, so thickeners don't tend to be recommended nowadays. If you wish to try this, seek your doctor's advice first.

Your doctor may recommend an anti-regurgitation formula, or an antacid combined with another medicine called an alginate – an example is Gaviscon Infant. Alginates form a foam barrier that floats on the surface of the stomach's contents, and should help the milk stay in your baby's stomach.

Reaction to cow's milk

If your baby is diagnosed with a cows' milk allergy, your doctor can prescribe a different type of infant formula known as extensively or fully hydrolysed formula.

This means that:

  • the milk proteins are broken down into smaller parts, making them easier to digest
  • it's much less likely that the cows' milk protein will cause an allergy

Many children outgrow their milk allergies.


Medicines are rarely needed for reflux in babies, and their benefits are uncertain.

However, if your baby's feeding problems are unexplained, or your baby is not gaining much weight or is distressed, you may be referred to a paediatrician, who may suggest a trial of medication – either ranitidine or omeprazole – to reduce the amount of acid their stomach produces.

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.