Colic and Excessive Crying: What Research Says About Causes and Interventions

By Birth & Baby University · Last updated: October 2026 · 8 min read

Colic is one of the most exhausting experiences of early parenthood and one of the least settled topics in infant medicine. Parents try gas drops, probiotics, formula changes, chiropractors and apps, and they receive conflicting advice from friends, the internet and sometimes clinicians. Postpartum doulas are often present during the daily crying peak, and the question is not only what to do but what to say. This article reviews what systematic reviews and a major clinical review conclude about colic: how it is defined, how common it is, which interventions have evidence and which do not, and how a doula can support a family without overstating a remedy.

Key takeaways

Quick answer: colic means excessive crying in a baby who is otherwise well, and it usually improves by three to four months. Its cause is not established. Reviews agree that parental education and reassurance and a clinician’s evaluation come first. The strongest evidence for a treatment is for a specific probiotic, Lactobacillus reuteri DSM 17938, in breastfed infants, though evidence is not consistent across reviews. Simethicone (gas drops) shows no benefit in the reviews examined, and none of the therapies is strongly recommended by an expert review because high-quality trials are lacking.

• A meta-analysis of 28 diary studies with 8,690 infants found average fuss and cry time of 117 to 133 minutes a day in the first six weeks, dropping to 68 minutes by 10 to 12 weeks, and colic by modified Wessel criteria in 17% to 25% of infants in the first six weeks, falling to 0.6% by 10 to 12 weeks.
• An individual participant data meta-analysis of four double-blind trials (345 infants) found L reuteri DSM 17938 reduced crying and fussing (adjusted mean difference at day 21 of -25.4 minutes) and increased treatment success, with dramatic effects in breastfed infants and insignificant effects in formula-fed infants.
• A systematic review of reviews and guidelines found probiotics had the strongest evidence for breastfed infants, manual therapies had weaker favorable evidence, simethicone showed no benefit or a negative effect, and one meta-analysis did not support proton pump inhibitors; national guidelines recommended education, reassurance and clinical evaluation but disagreed on other treatments.
• A Nature Reviews review concluded that owing to a lack of large, high-quality randomized trials none of the therapies discussed is strongly recommended.

What the research says

Definition and course. Wolke, Bilgin and Samara’s 2017 meta-analysis pooled 28 diary studies with 8,690 infants. Mean fuss and cry duration was stable at 117 to 133 minutes in the first 6 weeks and fell to 68 minutes by 10 to 12 weeks. Using modified Wessel criteria, colic occurred in 17% to 25% of infants in the first 6 weeks, 11% at 8 to 9 weeks and 0.6% at 10 to 12 weeks, lowest in Denmark and Japan, and the authors suggest defining excessive crying as above the 90th percentile of the review’s charts. The AAP’s guidance on responding to cries (updated February 2025) says there is no definite explanation for colic and that it most often means the child is unusually sensitive to stimulation or cannot yet self-console, with improvement as the baby matures. It says research has never shown simethicone (“gas drops”) or gripe water to work, and suggests non-medication options such as reconsidering a breastfeeding parent’s diet, slow feeding and ensuring burping, and for bottle-feeding a slower-flow nipple. Zeevenhooven and colleagues’ 2018 review notes little agreement on the definition, causes or best management of infant colic, discusses neurogenic, gastrointestinal, microbial and psychosocial factors, and stresses that a comprehensive history and physical examination in the absence of alarm symptoms guide a positive diagnosis and that parental education and reassurance are an important aspect of management.

What treatments have evidence. Ellwood, Draper-Rodi and Carnes’ 2020 systematic review of reviews and guidelines (32 studies) assessed manual therapy, probiotics, proton pump inhibitors and simethicone. It found high-level evidence that probiotics were most effective for reducing crying time in breastfed infants (reductions of 25 to 65 minutes over 24 hours), moderate to low quality evidence that manual therapies reduced crying time (33 to 76 minutes), moderate to low evidence of no benefit or a negative effect for simethicone, and one meta-analysis that did not support PPIs. Three national guidelines unanimously recommended education, reassurance, advice and guidance, and clinical evaluation of mother and baby, but had no consensus on other treatments, and the authors note the guidance did not reflect their findings on probiotics and manual therapy. The probiotic evidence centers on one strain. Sung and colleagues’ individual participant data meta-analysis (2018) of four double-blind trials, with 345 infants with colic, found the probiotic group averaged less crying and fussing at all time points (day 21 adjusted mean difference in change from baseline -25.4 minutes, 95% confidence interval -47.3 to -3.5) and was almost twice as likely to experience treatment success (adjusted incidence ratio 1.7). Effects were dramatic in breastfed infants and insignificant in formula-fed infants, where data were insufficient. The authors concluded it can be recommended for breastfed infants with colic. This sits against Zeevenhooven’s conclusion that none of the therapies is strongly recommended because of the lack of large, high-quality trials, so experts differ on how strong the evidence is. Manual therapies carry limited evidence of lower quality, and the reviewed abstract describes a low risk of serious adverse events for both approaches.

What this means for doulas

• Normalize without minimizing. Crying often peaks in the first six weeks and falls by 10 to 12 weeks. For a parent living through the evening hours, “it ends” helps only if paired with practical help.
• Prioritize evaluation. The reviews agree a clinician should rule out illness. Fever, vomiting, a bulging soft spot, crying when touched, poor feeding or weight gain are not colic (see Infant Crying Patterns: What Research Tells Us About the First Three Months).
• Do not recommend products as cures. Gas drops and gripe water have not been shown to work according to the AAP. Probiotic use is a conversation for the pediatric provider, and product quality and strain matter, as the evidence concerns a specific strain.
• Be careful with diet changes. The AAP mentions reconsidering a breastfeeding parent’s diet. Eliminating foods or stopping breastfeeding because of colic is a clinical decision and not supported as a general rule by the sources here.
• Support the caregivers. A parent at the end of their patience needs relief, not a longer list of things to try.

Putting the evidence into practice

1. Ask about the pattern. When does the crying happen, how long, what has been tried, what is the baby like between episodes?
2. Check red flags first, and make sure the baby has been seen by a pediatric provider.
3. Offer soothing options from the AAP list (rocking, walking, swaddling when safe, rhythmic noise, a warm bath) and help parents try them one at a time. See Swaddling and Infant Sleep: Benefits, Risks, and When to Stop.
4. Slow and burp feeds and review bottle flow, as the AAP suggests, and ask a lactation professional about breastfeeding if needed.
5. Plan breaks. Put the baby down safely, step away and call for help if frustration builds. Never shake a baby. Share this with every caregiver.

Limits and uncertainty

Colic is a descriptive label, not a diagnosis with a known cause, and definitions vary across studies. The probiotic trials are mostly small and concern one strain, so findings do not extend to other products, and who funded them was not examined. Reviews of reviews inherit the limits of the underlying reviews. This article draws on the abstracts of the research articles and the full AAP page. This article does not review evidence for dietary changes in detail (a 2012 review of dietary management exists but was not read), chiropractic and other manual therapy trials individually, or sleep and feeding interventions. Premature babies and babies with medical conditions need individual assessment.

The bottom line

Colic is common, distressing and temporary, with no established cause and no treatment that every expert strongly endorses. Reviews agree on education, reassurance and clinical evaluation, and the best-supported specific treatment is a particular probiotic strain for breastfed infants, though experts weigh the evidence differently. A doula’s best contributions are accurate expectations, a screening of red flags, gentle soothing and caring for the caregiver.

Birth & Baby University’s For Doulas page describes its postpartum doula training, recertification and mentorship for doulas who support families through crying and the early weeks. Confirm that any program meets your certifier’s, employer’s or state’s requirements before you enroll.

This article is for professional education. It is not medical, legal or tax advice. Check the standards of your certifying organization and the rules where you work. For concerns about a baby’s health, contact a pediatric provider or emergency services.

Sources and further reading

• Wolke D, Bilgin A, Samara M. Systematic review and meta-analysis: fussing and crying durations and prevalence of colic in infants. The Journal of Pediatrics (2017). Read the source
• American Academy of Pediatrics. Responding to Your Baby’s Cries (HealthyChildren.org, last updated February 2025). Read the source
• Zeevenhooven J, et al. Infant colic: mechanisms and management. Nature Reviews Gastroenterology & Hepatology (2018). Read the source
• Ellwood J, Draper-Rodi J, Carnes D. Comparison of common interventions for the treatment of infantile colic: a systematic review of reviews and guidelines. BMJ Open (2020). Read the source
• Sung V, et al. Lactobacillus reuteri to treat infant colic: a meta-analysis. Pediatrics (2018). Read the source

More for professionals: the Professionals Blog.