Are there any abilities, feats, or items that let you ignore the negative effects of drug consumption.
I'd very much like to be able to use aether and still be able to cast spells, for example.
(Anti)Paladin will remove the addiction aspect, but I'm not aware of anything to remove the penalties from the actual drug.
I was looking forward to having my Antipaladin being a heavy junkie, but the penalties for drugs are just way too costly.
Sounds like a houserule. The only place I ever heard of it is in the GMG.
Maybe some sort of feat that gives you immunities to drugs with DC's up to 18. That sounds fair to me, or some item that does that.
Psychics with the Psychedelia discipline don't get to completely bypass them, but they are rather resistant to them. If you want to be a Paladin/Antipaladin, as Heretek suggested, a dip into psychic will let you be really resistant to drugs. It works the other way around, too, if you want to be a psychic who takes a few levels in Paladin.
Self Perfection psychic can do self restorations to recover from the drug damage, at least.
See also the Mahathallah deific obediences which have a lot of drug related abilities.
I actually happen to be playing a self perfection psychic addicted to aether.
A ring of inner fortitude does a pretty good job of mitigating the damage, as do some of my class abilities, but I can't seem to find a way to benefit from the caster level increase and also be able to reliably cast my spells.