Medication review is an intervention with the potential to reduce drug-related problems (DRPs) in the elderly. This study aimed to determine the effect of pharmacists' medication reviews on geriatric patients. This study accessed two online databases, MEDLINE Complete and Scopus, and examined all studies published in English between 2019 and 2023, except for reviews. The studies included (1) participants over 65 years of age and (2) medication reviews conducted by pharmacists. The titles, abstracts, and full texts were reviewed for data extraction to determine whether the studies satisfied the inclusion and exclusion criteria. Forty-four of the initial 709 articles were included in this study. The articles included discussions on the incidence rates of DRPs and potentially inappropriate medications (PIMs) (n=21), hospitalization (n=14), medication adherence (n=9), quality of life (QoL) (n=8), and falls (n=7). Pharmacist medication reviews were associated with a reduced incidence of DRPs and PIMs, and improved adherence to medications. Patients' overall QoL is also increasing. However, pharmacist medication reviews were not strongly associated with decreased hospitalization or falls. A pharmacist's medication review may be a feasible intervention for reducing the incidence rates of DRPs and PIMs, regardless of whether it is performed as a sole intervention or supplemented with other interventions. The intervention was also effective in increasing medication adherence and QoL.