Background: Adverse drug events (ADEs) are a frequent cause of injury in patients. Our aim was to assess pharmacist interventions and their association with ADEs and potential adverse drug events (PADE). Methods: The search criteria: a published RCT, evidence of a pharmacist intervention, a comparison control group, and measurement of ADEs or PADEs. The information sources included MEDLINE, Embase, and two other databases through September 19, 2022. The risk of bias was assessed using the Cochrane tool for RCTs. A random-effects model for pooled studies was employed Results: Fifteen references meeting inclusion criteria were discovered. For ADEs, the pooled results showed a statistically significant benefit of pharmacist intervention in comparison to the control group (RR = 0.86; [95% CI 0.80-0.94); P = 0.0005. The heterogeneity was insignificant (P = 0.72; I 2 = 0%). Patients receiving a pharmacist intervention were 14% less likely for ADE than those who did not receive a pharmacist intervention. The estimated number of patients needed to prevent one ADE across all patient locations was 33. For PADEs, the pooled results did not show a statistically significant benefit for pharmacist intervention in comparison to the control group (RR = 0.79; [95% CI 0.47 – 1.32]; P =0.37.There was substantial heterogeneity in the pooled studies (P = 0.01; I 2 = 77%). However, there was a statistically significant subgroup difference (P = 0.005) for the intervention type. Conclusions: To our knowledge, this is the first systematic review and meta-analysis of RCTs seeking to understand the association of pharmacist interventions with ADEs and PADEs. The risk of having an ADE is reduced by a seventh for patients receiving a pharmacist care intervention versus no such intervention. This fraction could be higher for certain high-risk patients. The estimated number of patients needed to be followed across all patient locations to prevent one preventable ADE across all patient locations is 33. Also, a subgroup analysis of pharmacist intervention focus suggests that further research is necessary to fully understand the impact of TOC pharmacist intervention on PADEs. If validated, these findings have potential to significantly reduce drug-related morbidity and related healthcare costs.