Actually no, I meant that I know cough medicines that would cause it. Sorry for the confusion. I suppose, maybe, if your cough drops contain menthol and you've been eating like really a ton, there's a slight possibility that they're contributing to the dreams. Menthol is a kappa-opioid receptor agonist like salvinorin A, the main activate chemical in Salvia divinorum, and Salvia usually causes some pretty crazy and vivid dreams the night after you smoke it. I don't know if they would contribute to the theme of the dreams though, because Salvia has never given me nightmares, but I would imagine that if I did have a nightmare while in one of those vivid dreams it would be really intense and strange like the ones you've described. You could always try going without them for a few days and see if it changes anything, then you'll know for sure.