Adaptively controlling drive strength of multiplexed power from supply power rails in a power multiplexing system to a powered circuit is disclosed. A power multiplexing circuit in the power multiplexing system includes a plurality of supply selection circuits (e.g., head switches) each coupled between a respective supply power rail and an output power rail coupled to the powered circuit. The power multiplexing circuit is configured to activate a selected supply selection circuit to switch coupling of an associated supply power rail to the output power rail to power the powered circuit. In one example, the supply selection circuits each include a plurality of power switch selection circuits coupled to an associated supply power rail. The power switch selection circuits are configured to be activated and deactivated by a control circuit to adjust drive strength of a multiplexed supply power rail based on operational conditions, which can account for performance variations.