Tehran University of Medical Sciences Archives of Anesthesiology and Critical Care 2423-5849 0 0 2025 11 18 1360 1360 Hossein Karballaei Mirzahosseini Department of Clinical Pharmacy, School of Pharmacy, Semnan University of Medical Sciences, Semna,. Iran. Atabak Najafi Department of Anesthesiology and Critical Care, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Mojtaba Mojtahedzadeh Research Center for Rational Use of Drugs, Tehran University of Medical Sciences, Tehran, Iran. & Department of Clinical Pharmacy, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran. 2025 07 31 2025 08 10 Background: Infection with multidrug-resistant Acinetobacter baumannii has a high mortality rate. Some studies support the use of combination therapy with rifampin and colistin in the treatment of resistant Acinetobacter baumannii, but there is concern about the liver toxicity of high doses of rifampin in critically ill patients. Critically ill patients are more susceptible to liver side effects of drugs. The present cross-sectional study seeks to investigate the hepatic safety of rifampicin at a 1200 mg daily dose in combination with colistin. Methods: Following the acquisition of approval from the hospital's ethics committee, a cross-sectional study was conducted to assess the prevalence of hepatotoxicity associated with a daily dosage of 1200 mg of rifampicin. Patients who were treated with a rifampicin-colistin regimen and were admitted to the ICUs of Sina Hospital between April 2017 and February 2021 were identified for this study. Patients were screened for drug-related liver complications using the updated Roussel Uclaf Causality Assessment Method (RUCAM). Then the data was assessed using the SPSS software. Results: 60 patients were included in this study with an average age of 51.76 years. 40 patients (66.66%) were male and 20 (33.33%) were female. The studied patients had a mean weight of 72.56 kg, and their average rifampicin dose (based on their body weight) was 17.03 mg/kg. Results of ANOVA and Chi-square tests indicated that the values of main hepatic parameters like baseline aspartate aminotransferase (AST) (with a mean and standard deviation (SD) of 84.27±68.30), baseline Alanine transaminase (ALT) (with a mean and SD of 86.27±75.25), and baseline total Bilirubin (TBIL) (with a mean and SD of 1.16±0.788) were significantly related to the occurrence of drug-induced hepatotoxicity (P≤0.001). Conclusion: Critically ill patients take many drugs, some of which are categorized as hepatotoxic drugs and increase the risk of hepatic complications depending on the patient's underlying diseases. Results indicated that patients with elevated baselines of AST, ALT, and TBIL were more likely to suffer from drug-induced liver injury (DILI). It seems that a 1200 mg daily dose of rifampicin has a safe hepatic profile until meeting normal hepatic baseline requirements. https://aacc.tums.ac.ir/index.php/aacc/article/view/1360