Background: Extravasation injuries occurring in neonates can have severe consequences. Because many clinicians are not familiar with the vesicant-like effect of several commonly used medications, early extravasation wound management can be difficult. We aimed to share our experience with irritant-related and vesicant-related injuries leading to neonatal extravasation wounds. Methods: This retrospective study included 36 premature neonatal patients with extravasation wounds. Patients were classified into four groups based on extravascular staging and clinical wound conditions. We compared groups according to the following factors: sex, birth weight, prematurity, wound healing duration, days since the intravenous line was placed, wound severity, use of antibiotics, complications, treatment, type of intravenous fluid, and intravenous cannulation sites. Results: Neonatal birth weight was proportional to wound severity. Except in cases involving necrosis wounds, the lesion size increased with severity. Extravasation events occurred an average of 3.2 days after cannulation. Neonatal parenteral nutrition formulas and antibiotics acted as vesicants. Conclusion: Intravenous cannulation sites must be closely monitored in neonates, particularly during the first 3 days after cannulation. Monitoring is particularly important for larger neonates because intravenous fluid is administered based on body weight. Detailed knowledge about the vesicant fluid is required.