Methamphetamine (METH) is a powerful stimulant that affects neurochemical processes controlling heart rate, appetite, blood pressure, body temperature, and wakefulness, making it highly susceptible to abuse. Liver enzymes such as ALT, AST, ALP, and GGT are crucial for liver function. Albumin, a protein synthesized by healthy liver cells, serves as an indicator of chronic liver disease. Additionally, hepatocytes produce bile acids, which are essential for the secretion of bile salts into the bile canaliculi. Disruption in this secretion results in the accumulation of bile salts in the canaliculi, leading to intrahepatic cholestasis. METH-induced liver toxicity involves disruptions in hepatic metabolism, oxidative stress, and increased body temperature, affecting cellular processes such as cell division and the cell cycle and potentially accelerating liver cell apoptosis. The study explores the link between liver toxicity and hepatocyte damage in Iraqi males suffering from addiction. This is a case-control study, conducted at Ibn-Rushed Psychiatric Hospital in Baghdad from July 2023 to February 2024, involved 196 males, with addiction durations exceeding 24 months with varying degrees of methamphetamine (METH) addiction. The study included 187 healthy male controls with no history of drug addiction. Participants were aged 18 to 40 years. Diagnosis was confirmed using a drug test screening card administered by a specialist. The study included liver function tests (ALT, AST, ALP, and GGT), total bilirubin, and albumin concentration assessments. Significant differences were observed between the addicts and controls, particularly a marked decrease in serum albumin concentration in the addicted males. The ROC curve classification model at various thresholds demonstrated that liver enzymes, especially ALT, ALP, and GGT, exhibited increased sensitivity to METH addiction. A histopathological examination was conducted on a deceased 38-year-old male who had a six-year history of chronic amphetamine addiction to confirm liver injury and the resulting elevation of liver enzymes. The findings of this study indicate that METH greatly affects liver function, suggested to the importance of following a preventative measures and effective treatment approaches for monitoring METH addiction progress.