The effects of this particular potion appear to be temporary, if the "A Perfect Cure" ending is as it seems. Granted, we don't know if she was given an antidote, or reversal serum while asleep. If it isn't, maybe this comic will elaborate more? It's clear from Jess and Katie that the effects at least last for several hours if not more, maybe it's just scifantasy inconsistency shenanigans and that's totally fine.