<p>This study aimed to evaluate and compare the associations between these three drugs and amnesia-related adverse events using data from the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS). A retrospective analysis was conducted using FAERS data from the first quarter of 2004 through the first quarter of 2025. We extracted reports in which statins, PCSK9 inhibitors, or ezetimibe were listed as the primary suspected drugs and were associated with amnesia-related Preferred Terms (PTs). A total of 5833 amnesia-related reports were identified, including 4051 for statins, 1682 for PCSK9 inhibitors, and 100 for ezetimibe. Disproportionality analysis showed that statins exhibited positive signals in five of the six amnesia-related adverse events (except for “anterograde amnesia”). PCSK9 inhibitors were associated with a positive signal only for “memory impairment” (ROR = 1.50, 95% CI 1.42–1.58). Ezetimibe showed a positive signal for “amnesia” (ROR = 1.55, 95% CI 1.20–2.00) but an inverse association against “memory impairment” (ROR = 0.50, 95% CI 0.37–0.69). Time-to-onset analysis revealed that most adverse events occurred in the early stages of treatment. After adjustment for confounding factors, statins were associated with a significantly stronger signal intensity of “amnesia” (OR = 3.858) and “memory impairment” (OR = 3.363) compared to ezetimibe. Statins demonstrated the strongest signal intensity, PCSK9 inhibitors presented a relatively lower signal, and ezetimibe may demonstrate an inverse association in certain subtypes of amnesia. Most amnesia-related events occurred early during treatment, suggesting a possible time-dependent pattern. As a disproportionality analysis based on spontaneous reports, these findings only characterize signal patterns and do not establish causality or quantify incidence rates.</p>