Pharmacogenetics in Attention-Deficit/Hyperactivity Disorder (ADHD)

Background/Objectives: Attention-deficit/hyperactivity disorder (ADHD) is a highly heritable neurodevelopmental condition, and pharmacogenetic studies aim to clarify interindividual variability in treatment responses and adverse effects. Despite increasing research, the field remains fragmented. This review provides a bibliometric analysis of ADHD pharmacogenetics (2005–2025), identifying its intellectual foundations, thematic structure, and global distribution. Methods: A bibliometric search was conducted in Scopus and Web of Science, retrieving 711 documents published between 2005 and July 2025. Data were analyzed with the Bibliometrix R package and Biblioshiny interface, applying bibliometric mapping, Bradford’s Law, co-word analysis, and thematic mapping. Only peer-reviewed journal articles, books, and book chapters were included to ensure scientific rigor. Results: The dataset shows a modest annual growth rate but strong impact, with an average of 29.6 citations per article. Highly cited works converge into four domains: (i) clinical guidelines and pharmacological treatments; (ii) cognitive heterogeneity and subtypes; (iii) neurodevelopmental and genetic mechanisms; (iv) environmental and health-related influences. Geographically, the United States leads with 24.8% of publications, followed by Brazil, China, and European countries. Keyword analysis reveals two main clusters: a clinical–therapeutic pole (methylphenidate, atomoxetine, child) and a genetic–molecular pole (dopamine transporter, SNPs, genotype). Conclusions: ADHD pharmacogenetics shows consolidation with strong clinical and genetic cores but limited integration of comorbidity, adult populations, and non-stimulant treatments. Future research should prioritize multi-center cohorts, multi-omic designs, and stronger international collaboration to advance precision medicine in ADHD.