Introduction: Trenbolone is a potent anabolic steroid widely used in bodybuilding, despite its lack of approval for human use. Reports of adverse effects have increased, but systematic data on its health risks remain limited. This study aims to systematically review documented adverse effects of trenbolone in humans through published case reports. Methods: A structured review of case reports was conducted using PubMed, EMBASE, and CENTRAL databases, including studies up to 2024. The search strategy utilized Medical Subject Headings (MeSH) terms related to trenbolone. Inclusion criteria encompassed reports of adverse effects in humans with documented trenbolone use, while experimental studies, animal models, and reviews without original case data were excluded. Extracted data included patient demographics, trenbolone dosage, administration patterns, clinical presentation, toxicological findings, and affected organ systems. Results: A total of 23 case reports met the inclusion criteria. The most frequently reported complications involved the cardiovascular system (heart failure, myocardial infarction, ischemic stroke), hepatic system (cholestatic liver injury, hepatitis), renal system (nephropathy, acute kidney injury), and neuropsychiatric effects (psychosis, aggression, delirium). Most cases involved young male users, with trenbolone frequently sourced from unregulated markets. Toxicological confirmation was reported in only a minority of cases, complicating causality assessment. Conclusion: Trenbolone use is associated with severe health risks, particularly affecting the cardiovascular, hepatic, renal, and neuropsychiatric systems. The absence of clinical studies on its safety, along with widespread unregulated use, hinders risk assessment and patient management. Healthcare professionals should recognize potential adverse effects, promoting early detection and harm reduction. Further research is needed to clarify trenbolone’s long-term impact on human health.