Word of caution with phenergan (but know that I get all the really rare, nobody actually has this happen side effects): I was given phenergan to help with nausea/vomiting when I had lithium toxicity. It made me hallucinate. I was so out of it I didn't put it together until the next day or so and then I read the drug profile where it says that the drug can cause psychosis in those who are at higher risk for psychosis to begin with. I'm looking it up and it appears to be really rare. I was not on an AP back then and probably should have been but was refusing them after a few unpleasant (and also rare) reactions. I also was very, very sick from the lithium toxicity and was undoubtedly dehydrated and my electrolytes were messed up. I'd taken it before without any problems.

Like I said, this probably only happens to me but neither my dr nor my pdoc were aware of the notation about those prone to psychosis so it's good to know that going in.