A tongue piercing is the least painful body piercing in the industry.
The edges of your tongue has nerves, but the center of the tongue muscle does not which is why the piercing is not painful.
Some studios will offer to use 1% lidocaine but this will only numb the surface and does not improve upon the piercing experience.
Ice will also numb the tongue, but for only a brief period of time.
In our opinion, it is best not to try and numb the tongue for a piercing.