Background Hepatic insufficiency can affect patient safety and should therefore be considered during drug therapy. Hospital admission offers an ideal point to screen for patients at risk and to adjust drug therapy accordingly. Objective To assess the number of patients admitted to hospital with clinically elevated liver parameters. To identify high-risk patients in need of potential drug therapy adjustment to liver function by calculation of liver scores. Finally, to investigate whether pre-hospital medication needed adjustment to liver function. Setting Patients admitted to surgical wards of a tertiary teaching hospital. Method Surgical patients were included in a 3-month retrospective study. A pharmacist-led screening process, including recording of elevated liver parameters and calculation of liver scores (Child-Pugh-score, Model of End-stage Liver Disase [MELD], MELDNa), was used to assess frequency of hepatic insufficiency and patients potentially needing medication adjustment. Additionally, pre-hospital medication was checked for contraindications and correct dosage with regard to liver function. Main outcome measure Percentage of surgical patients with clinically elevated liver parameters at admission, percentage of patients with hepatic insufficiency potentially needing drug therapy adjustment, and percentage of pre-hospital drug intakes not adjusted to liver function. Results Of 1200 patients, 130 (11%) had at least one clinically relevant elevated liver parameter at hospital admission. Of these, need for drug adjustment to liver function was found for 16-36%, depending on the liver score used (equivalent to 2-4% of all patients), with the highest number of patients detected by the MELD- and MELDNa-score. Pre-hospital medication concerned 719 drug intakes and was contraindicated in 2%, dosage not adjusted in 3%, and evaluation not possible in 44% of all drug intakes due to lack of information on the drug. Conclusion A significant proportion of patients admitted for surgery have clinically elevated liver parameters and potentially need medication adjustment. A pharmacist-led screening already at hospital admission can support the identification of patients with clinically relevant elevated liver parameters and patients at risk by calculating liver scores under routine conditions. Evaluation of drug adjustment to liver function is challenging, since no data are available in routine resources for a considerable number of drugs.