Background and aims: Credible research emphasizes transparency, openness, and reproducibility. These characteristics are fundamental to promoting and maintaining research integrity. This aim of this study was to evaluate the current state of transparency and reproducibility in the field of addiction science. Design: Cross-sectional design Measurements: This study used the National Library of Medicine catalog to search for all journals using the subject terms tag: Substance-Related Disorders [ST]. Journals were then searched via PubMed in the timeframe of January 1, 2014 to December 31, 2018 and 300 publications were randomly selected. A pilot-tested Google form containing reproducibility/transparency characteristics was used for data extraction by two investigators who performed this process in a duplicate and blinded fashion. Findings: Slightly more than half of the publications were open access (152/293, 50.7%). Few publications had pre-registration (7/244, 2.87%), material availability (2/237, 1.23%), protocol availability (3/244 ,0.80%), data availability (28/244, 11.48%), and analysis script availability (2/244, 0.82%). Most publications provided a conflict of interest statement (221/293, 75.42%) and funding sources (268/293, 91.47%). One replication study was reported (1/244, 0.04%). Few publications were cited (64/238, 26.89%) and 0 were excluded from meta-analyses and/or systematic reviews. Conclusion: Our study found that current practices that promote transparency and reproducibility are lacking, and thus, there is much room for improvement. First, investigators should preregister studies prior to commencement. Researchers should also make the materials, data, analysis script publicly available. To foster reproducibility, individuals should remain transparent about funding sources for the project and financial conflicts of interest. Research stakeholders should work together toward improved solutions on these matters. With these protections in place, the field of addiction medicine can lead in dissemination of information necessary to treat patients.