To assess and compare the activity of pharmaceutical analysis on drug management in a geriatric acute care unit prior to and during the COVID-19 pandemic. This was a single-centre, observational, retrospective, and comparative cohort study. All Pharmacist Interventions (PIs) carried out in the unit between 27 January 2020 and 30 April 2020 were distinguished according to whether they were conducted prior to or during the first wave of COVID-19. The main outcome measure was the rate of PIs per patient and per line of treatment analysed. Other data collected were the drug class managed by the PI, the Drug Related Problems (DRP) identified, the nature of the advice given, and the acceptance rate by geriatricians A total of 355 stays were analysed, with PIs generated for 21.7% of the stays prior to COVID-19, and for 53.4% of the stays during the first wave (p=1.029 E-9). Among the 4,402 lines of treatments analysed, 54 PIs were carried out for prescriptions prior to COVID-19, and 177 during the first wave (p=0.002). DRPs were mostly related to anti-infectious drugs during the pandemic (20.3%, p=0.038), and laxatives prior to the pandemic (13.0%, p=0.023). The clinical impact of the PIs was mainly moderate (43.7%). The acceptance rate was 59.3%. A greater amount of DRPs were detected and more therapeutic advice was proposed during the first wave of COVID-19, with a focus on drugs used for the management of COVID-19 rather than geriatric routine treatments. The needs for clinical pharmacists were strengthened during the pandemic.