Alzheimer’s disease is closely associated with the interaction and aggregation of amyloid-beta (Aβ) peptides at neuronal membranes. Here, we use atomistic molecular dynamics simulations to investigate how two Aβ-interacting molecules, AC0107 and bexarotene, modulate Aβ–membrane interactions in a cholesterol-enriched POPC bilayer, with and without an oscillating GHz electric field. Five simulation conditions were examined, and peptide structural stability, membrane ordering, mobility, hydrogen bonding, radial distribution, and mass-density profiles were analyzed. The results reveal distinct modes of action for the two molecules. AC0107 preferentially localizes near the membrane–peptide interface and increases peptide–membrane hydrogen bonding, consistent with a barrier-like mechanism at the membrane surface. In contrast, bexarotene preferentially associates with the peptide when combined with the electric field, reduces peptide–membrane hydrogen bonding, and produces a more pronounced decrease in peptide mobility. The electric field therefore modulates the effects of the two compounds in different ways, enhancing the membrane-protective behavior of bexarotene while altering the response of AC0107. Overall, the simulations provide molecular-level insight into how small-molecule localization and external electric fields can regulate Aβ–membrane interactions.