Infant Distress Syndrome (Formerly Infantile Colic)

Why is my baby crying so much?

Crying is a normal part of infancy. Some babies, however, have recurrent and prolonged periods of crying or fussing that are difficult to settle, even though they otherwise appear well.

In Rome V (2026), this is now called Infant Distress Syndrome (IDS) rather than infantile colic. The change is important because the word “colic” suggests that the crying is caused by tummy pain, but this has not been proven. IDS is considered a disorder of gut–brain interaction, reflecting the complex interaction between the baby’s developing nervous system, gut and environment.

What Is Infant Distress Syndrome?

For clinical purposes, Rome V describes IDS as:

• Symptoms starting before 5 months of age
• Recurrent and prolonged periods of crying or fussing
• There is no obvious cause, and the crying cannot be easily prevented or settled by caregivers
• After appropriate assessment, the symptoms cannot be fully explained by another medical condition.

What about the famous “3-hour rule”?

You may have heard that colic means crying for more than 3 hours a day, on more than 3 days a week.

That was part of the older Rome IV research definition.

Rome V has moved away from making 3 hours the requirement for diagnosis. The committee recognised that some babies cry for less than 3 hours a day but still have significant distress and seriously affect family life.

Why Does It Happen?

There is no single proven cause.

IDS is thought to involve a combination of:

• The developing nervous system and ability to regulate crying
• Sensitivity to stimulation
• Developing sleep and feeding patterns
• Gut–brain interactions
• Gastrointestinal factors and the developing gut microbiome
• Family and environmental factors

The exact mechanisms are still being studied.

What Can Parents Do?

Helpful approaches include:

• Check whether your baby is hungry, tired, uncomfortable or overstimulated.
• Try gentle holding, rocking or other soothing techniques.
• Reduce excessive noise, light and stimulation.
• Maintain regular feeding and sleep routines where possible.
• Keep track of feeding, stools, vomiting, sleep and crying patterns.
• Avoid repeatedly changing formula or restricting foods without medical advice.

Most importantly, look after yourself too. A persistently crying baby can be extremely exhausting for parents. Ask your partner, family or trusted support person for help when you need a break.

❤️ The Good News

For most babies, excessive crying improves as they mature.

IDS does not mean that your baby has a damaged digestive system, and it does not mean that you have done something wrong as a parent.

Remember

Infantile colic is now called Infant Distress Syndrome in Rome V.

Crying does not automatically mean tummy pain, reflux or CMPA.

The important question is not simply “How much is my baby crying?” but:

“Is my baby otherwise well, growing and feeding normally, and are there any red flags?”