Well, actually yeah. LD50 stands for the Median Lethal Dose, or the amount of substance needed to kill off 50% of a population. It basically measures the toxidity of a substance.
Fun fact: Water actually has a LD50, who knew?
But antidotes for Snake Venom and say, Nerve Gas, are different. While antidotes for Snake Venom are usually mostly derived from the venom itself, almost like a vaccine (I'm not completely sure on the details, but basically if you use to much of the antidote, you'll just make things worse), but Nerve Gas antidote is a whole other substance.
The antidote for Nerve Gas, Atropine, counteracts the damage that Nerve Gas does, which is basically block the enzyme that help nerve signals travel (duh), but when used in too large doses, it solves your nerve problem but it actually has negative effects on the brain itself, not the nerves.
There is another antidote, called Pralidoxime chloride, that isn't toxic, but just reactivates the poisoned enzyme and makes them work again. It's slow though, so more unpopular, even though it's safer.
Sources: Wikipedia. HA, did you actually think I knew all this stuff?
But hopefully, Hinata doesn't use poisons. I just think it would be so un-Hinata, you know?