Can bactroban (mupirocin) be used on diaper rash?

yes,but: This depends on the rash. It will be helpful for a collection of bacterial related rashes producing pustular or blistering lesions. It will not be helpful for the common yeast that is a main cause of diaper rashes.

Agree w Dr. Ferguson: For diaper rash keep baby's skin clean & dry. Change diaper as soon as it's soiled or wet. For healing allow baby to go without diaper for periods of time so affected area can air out. Avoid tight diapers or airtight covers over diaper. Meds your Dr. might recommend include antifungal cream (for fungus), a steroid cream (for significant inflammation) or an antibiotic (for bacterial infection.)