**5. Conclusions**

Overall, our reviewed data suggest that caffeine is a possible adjuvant pharmacological strategy for the treatment of ADHD. The compiled preclinical data support the notion that caffeine improves ADHD-like symptoms of inattention and its related learning and memory impairments without affecting blood pressure and body weight. Our results are supported at the neuronal/molecular level, and strengthen the hypothesis that the cognitive effects of caffeine found in animal models of ADHD could be translated to humans diagnosed with the disorder, particularly during adolescence. Nonetheless, caution is needed when extrapolating potential effects identified in animal studies to human patients. In this work, studies that explored caffeine's effects on locomotor activity and impulsivity were contradictory, raising discrepancies that require further clarification. Although we consider that the reviewed results in this manuscript can potentially impact the scientific, pre-clinical, and clinical community and expand our knowledge regarding ADHD, more studies should be performed to validate our present knowledge while offering prospective clues to support caffeine as a therapeutic approach for the treatment of ADHD.

**Author Contributions:** J.C.V. contributed significantly to the conception and design of the manuscript, the acquisition of data, and data analysis and interpretation, agreeing to be responsible for all aspects of the work in ensuring that questions related to the accuracy or veracity of any part of the work are appropriately investigated and resolved. J.C.V., J.L.P., O.M.d.l.T. and D.R.-R. drafted the manuscript. D.R.-R. provided critical revision of the manuscript and final consent of the version to be published. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** We thank William J. Giardino from Stanford University for helpful comments on this manuscript.

**Conflicts of Interest:** The authors declare no potential conflict of interest regarding the research, authorship, and/or publication of this article.

#### **References**

