This review aimed to determine best nursing practice by systematically and critically reviewing the appropriate literature and expert guidelines. Using keywords and literature databases, over 480 journal titles were reviewed. Twenty-four articles and three expert guidelines were chosen. The majority of articles selected as evidence were Level IV - opinions of respected authorities based on clinical experiences, descriptive studies, case reports, or reports of experts. Two articles were Level I-II - experimental studies. Results of the review showed that traditional supportive interventions also have a body of evidence for their use. Although there is much research regarding neonatal abstinence syndrome (NAS), the majority of future research needs to be at a higher level of evidence. Nursing applications include obtaining evidence for best practice through diligent searches of the literature and expert guidelines.