A patient requires amphotericin B for a systemic fungal infection but has borderline renal function. Which immediate modification to therapy will most directly reduce nephrotoxicity while maintaining antifungal efficacy?

Reduce the amphotericin B dose by half without any formulation change and avoid monitoring kidney function since any dose reduction fully eliminates nephrotoxicity while preserving the same antifungal kill rate.

Administer amphotericin B as a concentrated rapid IV bolus to limit total exposure time, which eliminates nephrotoxic effects while preserving tissue penetration.

Add high-dose oral flucytosine alone to replace amphotericin B because flucytosine has no renal effects and as monotherapy produces the same fungicidal kinetics as amphotericin B in severe systemic fungal infections.

Switch from conventional amphotericin B deoxycholate to a liposomal amphotericin B formulation and ensure adequate pre-hydration, because liposomal formulations decrease renal exposure while preserving antifungal activity.