During transitions of care, including hospital discharge, patients are at risk of drug-related problems (DRPs).; To investigate the impact of pharmacist-led services, specifically medication reconciliation at admission and/or interprofessional ward rounds on the number of DRPs at discharge.; In this retrospective, single-center cohort study, we analyzed routinely collected data of patients discharged from internal medicine wards of a regional Swiss hospital that filled their discharge prescriptions in the hospital's community pharmacy between June 2016 and May 2019. Patients receiving one of the two or both pharmacist-led services (Study groups: Best Care = both services; MedRec = medication reconciliation at admission; Ward Round = interprofessional ward round), were compared to patients receiving standard care (Standard Care group). Standard care included medication history taken by a physician and regular ward rounds (physicians and nurses). At discharge, pharmacists reviewed discharge prescriptions filled at the hospital's community pharmacy and documented all DRPs. Multivariable Poisson regression analyzed the independent effects of medication reconciliation and interprofessional ward rounds as single or combined service on the frequency of DRPs.; Overall, 4545 patients with 6072 hospital stays were included in the analysis (Best Care n = 72 hospital stays, MedRec n = 232, Ward Round n = 1262, and Standard Care n = 4506). In 1352 stays (22.3%) one or more DRPs were detected at hospital discharge. The combination of the two pharmacist-led services was associated with statistically significantly less DRPs compared to standard care (relative risk: 0.33; 95% confidence interval: 0.16, 0.65). Pharmacist-led medication reconciliation alone showed a trend towards fewer DRPs (relative risk: 0.75; 95% confidence interval: 0.54, 1.03).; Our results support the implementation of pharmacist-led medication reconciliation at admission in combination with interprofessional ward rounds to reduce the number of DRPs at hospital discharge.