It appears that My First Infirmary is unable to clear NV addictions, such as Hydra addition.
In my case I was able to clear Fo3 addictions in Megaton's My First Infirmary, but not Hydra. Doc Church is able to cure the addiction though.
Load Order as follow:
[X] FalloutNV.esm
[X] DeadMoney.esm
[X] HonestHearts.esm
[X] OldWorldBlues.esm
[X] LonesomeRoad.esm
[X] GunRunnersArsenal.esm
[X] Fallout3.esm
[X] Anchorage.esm
[X] ThePitt.esm
[X] BrokenSteel.esm
[X] PointLookout.esm
[X] Zeta.esm
[X] TaleOfTwoWastelands.esm
[X] DragsVGUArmorBase.esm
[X] Project Nevada - Core.esm
[X] Project Nevada - Cyberware.esp
[X] Project Nevada - Rebalance.esp
[X] Project Nevada - Extra Options.esm
[X] iHUD.esm
[X] AWorldOfPainFO3.esm
[X] TTW_XPReduction.esp
[X] TTW_SuperMutantRebalance.esp
[X] TTW_StartupMenu.esp
[X] TTW_SpeechChecks.esp
[X] TTW_OutcastTrading.esp
[X] TTW_MoreCookingItems.esp
[X] Project Nevada - Cyberware Additions.esp
[X] Project Nevada - Rebalance Complete.esp
[X] Project Nevada - All DLC.esp
[X] Project Nevada - TTW.esp
[X] CASM.esp