<![CDATA[Background: Breast milk is the optimal source of infant nutrition, with formula feeding serving as an alternative when exclusive breastfeeding is not feasible. Feeding modalities may influence behavioral (crying), gastrointestinal (stool consistency), and dermatological manifestations. However, population-based comparative data in Indonesia remain scarce. Therefore, this study aimed to evaluate and compare the prevalence and patterns of symptoms between exclusively and non-exclusively breastfed infants. Methods: An analytical cross-sectional study was conducted at an outpatient clinic in Tangerang, Indonesia, utilizing structured parental interviews and clinical evaluations. A total of 290 healthy participants aged 0–12 months were enrolled, including 260 exclusively and 30 non-exclusively breastfed infants. Symptom severity over the preceding week was assessed using the standardized Cow’s Milk-related Symptom Score (CoMiSS™) framework, while chi-square and Fisher's Exact Tests were used to analyze symptom prevalence and co-occurrence patterns. Results: No significant differences were observed between the exclusively and non-exclusively breastfed groups in terms of abnormal stool consistency (8.5% vs. 10.0% ), increased crying duration (5.4% vs. 3.3% ), or skin rashes (41.2% vs. 40.0% ). There was no co-occurring symptom between stool consistency and crying in either group. No infant showed concurrent gastrointestinal and behavioral symptoms, with or without dermatological symptoms. Skin rashes were highly prevalent across the sample (~41%), but had no statistical association with gastrointestinal or behavioral manifestations. Conclusion: Feeding methods do not influence the clinical patterns of common infantile symptoms. Furthermore, stool abnormalities and excessive crying present as distinct entities rather than a unified cluster, offering reassurance to clinicians and parents managing these benign variations.]]>
