Ahhhh, welcome to my world!!
LSD makes me nauseous
every single time, without fail. I've just learned to cope with it and have found ways to manage it so that I can still enjoy the trip. And it's NOT anxiety-related nausea either because I do not ever suffer from anxiety, with or without acid. My LSD-nausea is purely a physical thing.
A small percentage of people get nausea from acid, and yeah, it's caused by the acid, not the ink or the cardboard or what you ate or didn't eat previously or anything like that. Believe it or not, it's the acid.
Having said that though, some people who are prone to anxiety may get nausea when they take acid, as an actual physical manifestation of their anxiety. But they should know within themselves if it's caused by the LSD or not.
Metaclopromide can help with the nausea, and here in Australia you can obtain it over the counter as a migraine treatment. Ginger tablets or sugared ginger can also help (although it never helped me personally). And good old antacids help a LOT as well, e.g. Mylanta syrup, or Gavascon chewable tablets etc.
I also find that eating something with bread also helps, like a sandwich with fresh salad (e.g. lettuce, tomato etc). NOTHING greasy like bacon or sausages, that will only make it worse.
And hey, if you find that nothing helps and it just gets worse each time you try acid, then maybe you should call it quits and admit that acid is not the drug for you...
Good luck, and PM me if you have any specific questions