Colic in Babies: What It Is and How Long It Lasts

Colic is long, intense, hard-to-soothe crying in a baby who is otherwise healthy and growing. The AAP says about one-fifth of all babies develop it, usually between the second and fourth weeks, and that colicky crying generally stops by 3 to 4 months, though it can last until 6 months. You may also hear it called the Period of PURPLE Crying. It is not caused by anything you did. Have your pediatrician check her once to rule out a medical reason, then the job is soothing what you can, putting her down safely when you can’t, and never shaking her.

What colic looks like

Most babies have a fussy stretch in the evening. The AAP says ordinary fussing peaks at about 3 hours a day by 6 weeks and then eases to 1 or 2 hours a day by 3 to 4 months. If she calms within a few hours and is fairly peaceful the rest of the day, the AAP says there is no reason for alarm. That evening pattern has its own guide here: the witching hour.

Colic is the bigger version. In the AAP’s words, if the crying “does not stop, but intensifies and lasts throughout the day or night, it may be caused by colic.” It describes colicky babies as crying inconsolably, often screaming, extending or pulling up their legs, and passing gas. The crying can come around the clock, though it often gets worse in the early evening.

The hardest part for me was her face. She looked like she was in pain, and nothing I did changed it. That turns out to be part of the description.

Colic and PURPLE crying are the same thing

If your hospital sent you home with a purple leaflet, this is what it meant. Cleveland Clinic says of colic, the witching hour and purple crying: “all these terms describe the same thing.” PURPLE is an acronym for what the crying is like:

P, peak of crying. She may cry more each week. Cleveland Clinic says this often peaks during the second month.
U, unexpected. It comes and goes for no clear reason.
R, resists soothing. She may not stop no matter what you try.
P, pain-like face. She can look like she’s in pain even when she isn’t.
L, long-lasting. Several hours a day. Cleveland Clinic says five hours or more is not uncommon.
E, evening. Late afternoon and evening are the worst.

Cleveland Clinic notes that some experts avoid the word “colic” because it sounds like an illness, and adds, “There’s nothing wrong with a ‘colicky’ baby.” The word “period” is in the name on purpose. It has a beginning and an end.

When does colic start, peak and stop?

	What the sources say
Starts	Usually between the second and fourth weeks (AAP); around 2 weeks (Cleveland Clinic)
Peaks	Fussing peaks at about 3 hours a day by 6 weeks (AAP); crying often peaks in the second month (Cleveland Clinic)
Stops	Generally by 3 to 4 months, but it can last until 6 months (AAP); ends around 3 to 5 months (Cleveland Clinic)

So if you are at week five and it is getting worse, you are probably on the way up the hill, not doing it wrong. Our 6-week-old baby guide covers that peak week on its own.

What causes it?

Nobody knows for certain. The AAP says “there is no definite explanation,” and that most often colic “means simply that the child is unusually sensitive to stimulation” and can’t yet settle her own nervous system.

It also lists a few specific causes worth asking about. In breastfed babies, colic is sometimes a sign of sensitivity to a food in the nursing parent’s diet. Sensitivity to milk protein in formula is rare. And colicky behavior “may signal a medical problem, such as a hernia or some type of illness.” That last one is the reason for the pediatrician visit.

What helps

The AAP’s first step is the check-up: “consult your pediatrician to make sure that the crying is not related to any serious medical condition.” Then ask which of these to try.

Motion and closeness. Walk her in a baby carrier. The AAP says the motion and body contact will reassure her even if the discomfort continues.
Steady sound. Rock her, run the vacuum in the next room, or use a fan or white-noise machine. A fan-based one like the Yogasleep Dohm Uno does the same job as the clothes dryer without the laundry. The AAP adds: never put a baby on top of the washer or dryer.
A pacifier. Some breastfed babies refuse it. For others the AAP says it brings instant relief.
Tummy-down across your knees with a gentle back rub. If she falls asleep like that, move her to her crib on her back.
A swaddle in a large, thin blanket.
Don’t overfeed. The AAP suggests waiting at least 2 to 2½ hours from the start of one feed to the start of the next.
Diet changes, only with your pediatrician. If you’re nursing, the AAP suggests talking to the doctor first, cutting one food at a time and allowing about two weeks to see a change. For formula, it says less than 5% of colicky crying is caused by food sensitivity, so a switch is a doctor’s call.

Cleveland Clinic adds skin-to-skin, a walk, singing and a warm bath, and is honest about the limit: “soothing doesn’t always work.” Betteroo has a longer look at which shelf remedies hold up in trials if you’re standing in the pharmacy aisle wondering.

The crying plan: when you’ve hit your limit

Write this down before you need it, and show it to anyone who looks after her.

The AAP’s abusive head trauma page says healthy, well-loved babies may cry for 1 to 2 hours every day, and some cry longer. When you feel yourself getting angry:

Take a deep breath and count to 10.
Put her in a safe place, such as a crib or playpen with no blankets or stuffed animals.
Leave the room and let her cry alone for about 10 to 15 minutes.
Do something that calms you. Music, a phone call to a friend, the dishes.
Check on her after 10 to 15 minutes, but don’t pick her up until you feel calm.

A baby crying alone in a safe crib for ten minutes is safe. The AAP is blunt about the alternative: “a baby should never be shaken. Shaking an infant hard can cause blindness, brain damage or even death.” It asks that everyone who cares for her knows this, including partners, grandparents and sitters.

Weeks of this wear a person down. The AAP says to tell your own doctor if you are feeling depressed or having trouble with your emotions, and our guide to baby blues versus postpartum depression covers the signs.

When to call the pediatrician

Call for a first check whenever the crying worries you. Cleveland Clinic lists these as reasons to call during the crying months:

a fever of 100.4°F (38°C) or higher
crying more when you move, touch or hold her
vomiting
refusing to eat or drink for more than eight hours
areas of swelling
looking or acting differently in any way
poor weight gain
changes in her poop

When the crying eases and sleep is next Betteroo builds a personalized sleep plan around your baby's age, ready for when the evenings calm down. Take the free sleep quiz →

FAQ: colic in babies

How long does colic last each day?

It varies. The AAP describes ordinary fussing peaking at about 3 hours a day. Cleveland Clinic says babies in the PURPLE crying period can cry five hours a day or longer.

Did I cause my baby’s colic?

No. The AAP says there is no definite explanation for it, and Cleveland Clinic calls it a normal, healthy part of development that every baby goes through to some degree.

Is it okay to let a colicky baby cry in the crib?

For a short break, yes. The AAP says it’s OK to lay her on her back in the crib or another safe place and leave the room for a few minutes when no one else can help.