Memory wipers have only appeared twice in the series, on most other occasions, Jorgen and other fairies simply use their wands to wipe memories. It's unknown why a separate device was created when wands can do the same exact thing. Memory wipers appear to be used when a godchild's fairies are discovered, they violate a serious rule (eg. Making a secret wish), or causing his/her fairies to quit being godparents.
In it's first appearance, "The Secret Origin of Denzel Crocker!", it was used by Jorgen and several fairy agents when Denzel Crocker's fairies were exposed. When Jorgen overused it on ten year old Denzel Crocker, it caused permanent physical disfigurement to him. The 1970's Cosmo also mistakenly uses it on himself and Wanda, wiping their memories of being Crocker's godparents.
A higher powered version was later successfully used on Timmy in Fairy Idol, after he had managed to avoid losing his memory with the first one. The Extra-Strength wiper's power is supplemented by something called "Forgeticen"
Not much is known about Forgeticen, as it is only briefly mentioned at the end of "Fairy Idol". It appears that it is what strengthens the effects of the memory wiper. Jorgen is required to read a disclaimer before he can use it on someone due to supposed side effects.
- It is a reference to the Neutralizers from the Men In Black film series.
- It appears that the effects of the memory wiper can wear off if the person is reminded of what their minds got wiped of, as shown in "The Secret Origin of Denzel Crocker!". The memories of Cosmo and Wanda being Denzel's fairies and how he lost them seem to slowly come back to them as the episode progresses.
- As demonstrated by the aforementioned episode, "The Secret Origin of Denzel Crocker!", it has the potential to cause permanent physical damage if the device is used too much on a resisting godchild, such as Mr. Crocker.
- The disclaimer for Forgeticin is the second time real-life politics are mentioned in the series (Democratic presidents). The first time is in "The Secret Origin of Denzel Crocker!" when Timmy travels back to 1992 and one of the cars has a sticker for Clinton/Gore.