My son has just smeared a second tube of diaper rash cream over the carpet, and I was looking for an easier clean. The first time we just rubbed and rubbed with cloth and paper towels, then steam cleaned the carpet (which actually didn't help it at all). Eventually the stuff rubbed off and you can't tell where it got rubbed it. But we have a light colored carpet. I think darker carpets may stain if it is in there too long.
Since the cream is water resistant you could try soapy water, using a laundry detergent or dish soap, either way be prepared for lots of scrubbing.
Since the cream is water resistant you could try soapy water, using a laundry detergent or dish soap, either way be prepared for lots of scrubbing.