Should i rub alcohol on a piercing daily to help prevent keloids?

No: Keloids result from an excessive bodily reaction to a wound. Unlike normal healing which lays down scar tissue(collagen) to close a wound, a keloid forms when the degree & magnitude of this process is excessive. And unlike a hypertrophic scar which is an excessive amount of scar tissue within the confines of the injury, a keloid results when the process extends into the normal surrounding tissue.

Perhaps: Alcohol may be useful in removing excess oils that can cause inflammation, the trigger for keloid growth, but your local immune response is what triggers the collagen production to grow keloids. I have seen keloids shrink and flatten with carboxytherapy. Other effective methods may include steroid injections, or surgery.