Mupirocin is an antibacterial agent, and cold sores are viral, so it is not effective for treating cold sores.
Bactroban is an antibacterial agent, and cold sores are viral, so it is not effective for treating cold sores.
Bactroban is not effective for viral cold sores.
Peroxide is damaging to newly growing skin, so using it on a cold sore may delay healing.