A polymer composite comprising a thermoplastic polymer compounded with a phenolic antioxidant, an organo-disulfide antioxidant, and a silver-based antimicrobial agent. The specified combination of antioxidant stabilizers is superior in inhibiting undesirable discoloration of thermoplastic polymers in the presence of compounded silver-based antimicrobial agents. A process of preparing such a composite, comprising compounding the phenolic antioxidant and organo-disulfide antioxidant with the thermoplastic polymer prior to compounding the silver-based antimicrobial agent with the thermoplastic polymer.