Suspected Drug-Induced Hepatocellular Injury Following Use of an Unregulated Injectable Product Marketed as Retatrutide: A Case Report

Unregulated injectable preparations marketed as investigational weight-management agents raise concerns about product identity and safety.A 39-year-old man presented with fatigue, nausea, anorexia, and right upper quadrant discomfort beginning approximately 25 days after the first reported injection of a product marketed as retatrutide.At the initial clinical evaluation (day one), alanine aminotransferase (ALT) was 328 U/L and aspartate aminotransferase (AST) was 156 U/L; the R ratio was 9.87, indicating a hepatocellular biochemical pattern.Bilirubin and international normalized ratio (INR) were normal.Initial viral and autoimmune investigations were unrevealing, although hepatitis C RNA was not obtained.The patient was administered the fifth and final injection after symptom onset.His ALT declined from 328 to 118 U/L over 14 days after presentation, corresponding approximately to days five to 19 after the final reported injection, and normalized by week six.The course was compatible with, but did not establish, exposure-associated liver injury.Incomplete exclusion of alternative causes and the absence of product verification limited causal attribution.