Infant colic typically lasts about two to three months. It most often begins late in the first month of life, peaks in intensity around six weeks, and lessens significantly after three to four months of age. While those weeks can feel endless, colic is a temporary phase with a predictable arc.
The Typical Colic Timeline
Colic follows a surprisingly consistent pattern across most babies. Crying episodes usually appear in the second or third week after birth, then escalate quickly. By about six weeks old, the crying is at its worst. This is often when parents first seek help, because the sheer volume and duration of the episodes can feel alarming.
After that six-week peak, things gradually improve. The bouts of intense crying lessen after three to four months of age. For some babies, the change is dramatic, almost like flipping a switch. For others, it’s a slower fade where crying episodes get shorter and less frequent over several weeks. Either way, the vast majority of colicky babies are past the worst of it by four months old.
How Colic Is Defined
Doctors diagnose colic using what’s called the “rule of three”: crying more than three hours per day, more than three days per week, for longer than three weeks. The crying typically happens in the late afternoon or evening, and the baby is otherwise healthy, feeding well, and gaining weight normally. If your baby cries intensely but doesn’t meet that threshold, they may just be going through a normal fussy period, which also peaks around six weeks and resolves on its own.
The key distinction is that colic isn’t caused by pain, hunger, or illness. It’s a pattern of excessive crying in an otherwise thriving infant. That’s what makes it so frustrating for parents: there’s no clear problem to fix.
What Helps During Those Weeks
No single treatment reliably stops colic, but a few strategies have some evidence behind them.
For breastfed babies, a maternal low-allergen diet (cutting dairy, eggs, nuts, and wheat) helped reduce crying in one study, with 74% of infants showing improvement compared to 37% of infants whose mothers ate their normal diet. That said, a Cochrane review looking across all the dietary research concluded there wasn’t enough strong evidence to recommend any specific dietary change as a standard approach. If you want to try eliminating dairy from your diet, give it about two weeks to see whether it makes a difference.
A specific probiotic strain, Lactobacillus reuteri, has shown promise in several studies. In one trial, babies receiving the probiotic cried an average of 60 minutes per day by the end of the study, compared to 102 minutes in the placebo group. Another study found even more dramatic results: crying dropped from over six hours a day to just 35 minutes after three weeks of treatment. These results were strongest in breastfed infants, and the evidence for formula-fed babies is less clear.
Beyond those options, the classic soothing techniques still matter. Swaddling, rhythmic motion, white noise, and skin-to-skin contact won’t cure colic, but they can shorten individual crying episodes and help you get through the toughest evenings.
The Toll on Parents
It’s worth acknowledging what colic does to the people caring for the baby. A study of 380 mothers found that those with colicky infants had significantly higher depression, anxiety, and stress scores than mothers of non-colicky babies. As depression scores increased, maternal attachment levels decreased. This isn’t a personal failing. It’s a predictable response to weeks of inconsolable crying.
If you’re in the middle of it, building in breaks is essential. Putting a crying baby down in a safe space like a crib and stepping away for five or ten minutes is not neglect. It’s a reasonable strategy that pediatricians actively recommend, especially when frustration is building. Partners, family members, or friends who can take a shift, even for an hour, can make a real difference in getting through the peak weeks.
What Colic Doesn’t Mean
Colic is not a sign that something is wrong with your baby’s health, and it’s not a reflection of your parenting. Babies who are colicky grow, develop, and thrive at the same rate as their peers in infancy.
However, one large study tracking children over several years found that infants with colic scored slightly lower on developmental measures at age five and had somewhat higher rates of internalizing behaviors (like anxiety and withdrawal) at ages three and five. The differences were small but statistically significant, and researchers noted that colic combined with early sleep problems may be a risk factor worth monitoring. This doesn’t mean a colicky baby will have problems later. It means that if you notice behavioral concerns as your child grows, the colic history is useful context to share with your pediatrician.
When the Crying Signals Something Else
True colic happens in a baby who is otherwise completely healthy. If your baby has a fever, is vomiting forcefully, refusing to eat, losing weight, or has blood in their stool, that’s not colic. Those symptoms suggest a different condition, like a milk protein allergy, reflux, or an infection, that needs medical evaluation. Similarly, if the intense crying starts suddenly after three months rather than following the typical pattern of beginning early and gradually improving, it’s worth getting checked out rather than assuming it’s a late case of colic.