It is now possible to become addicted to fire ant nectar as well as the normal ant nectar, though the 5% chance is one of the lowest addiction rates of any consumable in the game. It is further reduced by Chem Resistant, Old World Gourmet (fnvdm) and Big Brained (fnvowb) perks producing a very small 0.75% chance (likely rounded up to 1%) of addiction. The player will still become addicted with a 100% chance after frequent use, this is due to the UMON effect. The effect can be avoided through the use of the Logan's Loophole trait however.
Ant nectar addiction used to be incurable due to a bug, but this was fixed in Fallout: New Vegas patch 184.108.40.206x. The console command Player.RemoveSpell 0006dc6e will immediately remove the addiction on the PC version.