Colic and unsettled evenings in newborns: why it happens and what can help

Sleep · Updated July 2026 · All articles

If you have a newborn who is inconsolably unsettled most evenings despite being fed, winded, changed, and held, you are not doing anything wrong. This pattern, which peaks around week 6 and resolves by 3 to 4 months in most babies, is so common it has its own name: colic. It affects around 1 in 5 babies equally across feeding methods, birth weights, and parenting approaches. This article covers what colic actually is, what the research says about causes and remedies, what genuinely helps in the moment, and what to expect from the weeks ahead.

What colic is: the rule of three

Colic has a clinical definition that helps distinguish it from ordinary newborn fussiness: crying for more than 3 hours a day, more than 3 days a week, for more than 3 weeks, in an otherwise healthy, well-fed baby. This is the rule of three, and it is worth knowing because it confirms that the pattern you are seeing is a recognized, well-described phenomenon rather than an indication that something is wrong with your baby or your care.

Importantly, colic is a description of a crying pattern, not a diagnosis of a specific underlying cause. It tells you about the frequency and intensity of the crying, not why it is happening. This distinction matters because it means there is no single treatment for colic; what can be done is either address potential contributing factors or manage the experience of the episodes themselves.

The evening cluster is one of the most characteristic features of colic. Babies who are settled through much of the day often begin a prolonged crying period in the late afternoon or evening, typically between around 5pm and 10pm. This timing is consistent enough that it has led to theories about sensory overload at the end of a stimulating day, though as with most aspects of colic, this theory is not definitively proven.

What colic is not (not a sign of bad parenting or wrong feeding)

This section exists because the experience of having a colicky baby is often accompanied by a deeply uncomfortable feeling that you must be doing something wrong. You are not. Colic is equally common in breastfed and formula-fed babies, in babies of first-time parents and experienced ones, in babies born to calm households and busy ones. There is no feeding approach, routine, or parenting style that prevents colic or causes it.

The distress of watching your baby cry for hours and being unable to console them is real and significant, and it is entirely separate from anything you are or are not doing. Colic does not damage babies. Studies on children who experienced colic as infants show no lasting effects on attachment, emotional development, or the parent-child relationship. The difficulty is primarily yours, as the parent in the room at 8pm with a screaming baby: it is exhausting and emotionally depleting, and that deserves acknowledgement.

Theories about what causes it

Researchers have been studying colic for decades and still do not have a single agreed explanation. The most compelling current theory involves gut microbiome immaturity. Studies have found consistent differences in the gut bacteria of colicky babies compared to non-colicky ones, specifically lower levels of Lactobacillus species. Whether this difference causes the crying or is an associated feature is still being investigated, but it has driven interest in probiotic interventions.

A second theory focuses on gastrointestinal motility: the way the immature gut processes and moves gas and food. Newborns' digestive systems are still calibrating, and some evidence suggests colicky babies show differences in gut movement. This is consistent with the observation that many colicky babies seem to get some temporary relief from position changes or abdominal pressure.

A third framing is the PURPLE crying framework, developed by child development researchers. PURPLE stands for Peak of crying (weeks 2 to 4, with a peak around 6 weeks), Unexpected, Resists soothing, Pain-like face, Long-lasting, and Evening clustering. This model emphasises that the crying pattern is a normal developmental phase, not a medical problem. The research behind it shows this crying pattern is universal across cultures and appears even in babies born into very different environments, which strongly suggests it is developmental rather than circumstantial.

What the evidence says about interventions: probiotics, simethicone drops, maternal diet

Simethicone drops, sold in the UK as Infacol, are among the most widely used colic remedies. Simethicone works by breaking up gas bubbles, which is why it is often given to babies thought to have wind as a contributing factor. Clinical trials, however, have not consistently shown simethicone to outperform placebo for colic. This does not mean it is harmful; it just means the evidence does not support it as an effective treatment for colic specifically. If you have tried it and it seems to help your baby, that is worth noting: individual responses vary and placebo effects in the parent (reduced anxiety leading to more settled handling) are real.

Gripe water has been used for generations and has similarly weak clinical evidence. Its formulations vary by brand and country. Some older formulations contained alcohol or sugar, which are no longer considered appropriate for newborns. Modern gripe water formulations are generally safe but there is no robust evidence they reduce colic crying duration or frequency.

Probiotic supplementation with Lactobacillus reuteri DSM17938 is currently the intervention with the most promising, though not yet definitive, evidence. Several randomised trials have found that breastfed colicky babies given this probiotic strain showed a meaningful reduction in daily crying time compared to placebo. The effect has not been replicated as consistently in formula-fed babies, and the overall evidence base is still developing. Your health visitor can help you decide whether a trial is appropriate for your situation.

Maternal dietary elimination, specifically removing dairy, is often suggested for breastfed colicky babies. The evidence for this in the general colic population is modest and inconsistent. Cow's milk protein allergy (CMPA) is a separate condition from colic and typically comes with additional symptoms: blood or mucus in stools, significant reflux or vomiting, a skin rash, or poor weight gain. If your baby has these symptoms alongside the crying, a supervised dairy elimination trial of two to four weeks is worth discussing with your GP or health visitor. If the only symptom is evening crying, the evidence does not strongly support dairy elimination and it carries its own cost in terms of maternal nutrition and the complexity of maintaining an elimination diet while exhausted.

The hold and other in-the-moment strategies

While the evidence on colic remedies is mixed, there is a consistent body of parent experience and some clinical support for positioning and motion strategies during episodes. The colic hold is the most widely described: hold your baby face-down along your forearm, with their tummy resting on your arm, their head near your elbow, and their legs straddling your wrist. This position places gentle pressure on the abdomen and many babies settle, at least partially, when held this way. It also allows you to gently sway or rock while holding them, combining the physical pressure with the motion effect.

Skin-to-skin contact is another strategy with good theoretical grounding. Being held against a warm body slows a baby's heart rate, regulates their temperature, and promotes the release of oxytocin. During a colic episode this may not stop the crying immediately but it provides a consistently regulatory environment that tends to shorten episode length compared to leaving the baby in a cot or bouncy chair.

A warm bath, offered during a particularly prolonged episode, is reported by many parents as a reliable circuit-breaker. The warmth appears to have a muscle-relaxing effect and the sensory shift of being in water can interrupt the crying cycle. It is not a solution for every baby or every evening, but it is worth trying if you have not.

White noise, motion, and babywearing

White noise and rhythmic motion are among the most reliably effective in-the-moment strategies for unsettled newborns, colicky or otherwise. Newborns spent nine months in an environment of constant sound (the maternal heartbeat, digestive sounds, and muffled external noise) and motion. The relative silence and stillness of a cot or pram can feel unfamiliar and under-stimulating. White noise at a volume similar to a quiet shower, played at a safe distance, mimics the continuous background sound of the womb and is calming for many babies.

Rhythmic motion, whether rocking in arms, using a bouncy chair, a baby swing, or being carried, works on a similar principle. The vestibular system (the part of the inner ear that processes movement) is particularly responsive in newborns. Slow, rhythmic motion has a settling effect that is independent of the feeding or holding relationship. This is why pram walks often work when nothing else does: the continuous gentle motion and outdoor sensory environment shift the baby's state.

Babywearing during the colicky evening window is practically useful for many families because it combines motion, warmth, and closeness while keeping the parent's hands free. A well-fitting soft structured carrier or ring sling in a face-in, tummy-to-tummy position for a newborn allows you to move around, prepare dinner, care for an older child, or simply stand in front of a sink with running water (which many colicky babies find very settling) while your baby is in the motion-and-closeness environment that helps most. Carrier safety guidelines for newborns apply: keep the airway visible, the chin off the chest, and the baby in a supported seated position.

When it peaks and when it ends: week 6, gone by 3 to 4 months

One of the most genuinely comforting things about colic is that it follows a predictable arc. Crying increases from birth, peaks at around 6 weeks of age, and then gradually declines. By 3 months most babies have significantly less colic, and by 4 months the pattern has resolved in the vast majority of cases. This timeline holds across studies in different countries and different populations.

Knowing the shape of the curve matters when you are in the middle of it. If your baby is 4 weeks old and the evenings feel unbearable, you are approaching the worst of it. If your baby is 7 weeks old, you have likely passed the peak. The resolution is not usually sudden but rather a gradual shortening and lightening of the evening unsettled period over a series of weeks.

If excessive crying continues well beyond 4 months, or if your baby has any symptoms beyond the crying (poor weight gain, blood in stools, a rash, significant vomiting), speak to your health visitor or GP. These may indicate an underlying cause that warrants investigation rather than the standard developmental colic pattern.

Survival strategies for parents: asking for help and taking shifts

The physical and emotional toll of colic is real and deserves to be named. Spending two to four hours every evening with a baby who cannot be consoled is exhausting in a way that is qualitatively different from ordinary newborn tiredness. It often comes at the end of an already difficult day, and it can begin to feel like it will never end even though it will.

The most practical advice is to share the burden where possible. If you have a partner, take shifts so neither of you is handling the whole episode every night. Even thirty minutes off, putting on headphones and going to another room, makes a measurable difference to your ability to cope. If you are parenting alone, identify one or two trusted people who can come and hold the baby for an hour while you rest. This is not a small ask to make; it is a reasonable request during a temporary but genuinely difficult period.

It is also worth being explicit with yourself about the difference between "nothing I do makes this better" and "I am failing." These are not the same thing. Colic does not respond reliably to any particular parenting intervention because it is primarily a developmental phase, not a problem you are causing. You are not failing. You are witnessing a normal if very uncomfortable stage of newborn development, and the most important thing you can do is stay safe, stay as rested as possible, and wait it out.

Frequently asked questions

What is colic exactly?

Colic is defined by the rule of three: crying for more than 3 hours a day, more than 3 days a week, for more than 3 weeks, in an otherwise healthy baby. It typically peaks around week 6 and resolves by 3 to 4 months in most babies. Colic is a description of a crying pattern, not a diagnosis of a specific cause. It affects roughly 1 in 5 babies and is equally common in breastfed and formula-fed infants.

What causes colic?

The honest answer is that researchers are still not certain. Leading theories include gut microbiome immaturity (colic is associated with differences in gut bacteria), sensitivity to sensory stimulation at the end of a long day, gastrointestinal motility issues, and the normal developmental PURPLE crying period. None of these theories fully explains every case. Cow's milk protein allergy (CMPA) can cause similar crying patterns in a subset of babies, but colic and CMPA are not the same thing and CMPA typically comes with additional symptoms such as reflux, blood in the stool, or a rash.

Does eliminating dairy from my diet help colicky breastfed babies?

Maternal dietary elimination has modest and inconsistent evidence. For the general colic population it is unlikely to make a significant difference. However, if your baby also has other symptoms of cow's milk protein allergy such as mucous in their stools, significant reflux, a skin rash, or blood in stools, a two to four week dairy trial under the guidance of your health visitor or GP is worth considering. Eliminating dairy without clinical reason is not recommended, as it can affect maternal nutrition.

Do colic drops help?

Simethicone drops (Infacol) have not consistently outperformed placebo in clinical trials for colic. Gripe water has similarly weak evidence. Probiotic supplementation with Lactobacillus reuteri DSM17938 has shown some benefit in reducing crying time in breastfed babies with colic in several studies, though the effect is modest and has not been replicated consistently in formula-fed infants. Your health visitor can help you weigh up what is worth trying in your specific situation.

What actually helps in the moment during a colic episode?

Movement and sound are the most consistently effective in-the-moment strategies. Holding your baby in the colic hold (baby face-down along your forearm, tummy on your arm, head near your elbow), gentle rhythmic motion such as rocking or swaying, white noise or the sound of running water, a warm bath, or skin-to-skin contact are all reported by parents as helpful. What works varies between babies. This is also why babywearing in the evenings can be very practical: it keeps your hands free while offering the movement and closeness the baby needs.

When does colic end?

Colic typically peaks at around 6 weeks of age and resolves by 3 to 4 months. By 4 months the vast majority of babies have significantly less or no evening crying. This timeline can feel endless when you are in the middle of it, but knowing there is a natural end date is genuinely reassuring. If excessive crying continues well beyond 4 months, or if your baby also has other symptoms, speak to your health visitor or GP to rule out any underlying cause.

This article is for general information only. If you have concerns about your baby's crying or health, speak to your health visitor or GP.