I joined the forum yesterday and have been reading for hours. I recommend you read the entire SN megapost; it's right there that they mention "drug interactions." When you mix chemicals with other chemicals, or drugs with other drugs, an interaction occurs that, when it enters our system, produces a certain result. In any case, I would recommend taking more quetiapine and stopping the antihistamine.
Sorry for my bad English, I'm using a translator because I'm too tired for do it by myself.
I really want to pass out as fast as possible after ingesting the SN, are you sure I wouldn't need the promethazine? It's very helpful especially when I take higher doses 125- 250mg. But I don't wanna fuck this up so I don't wanna take too much. I just wanna know if it'll disrupt and complicate the process or quicken it ig.
It might be a good idea to use a timer or alarm for several days to see how long it takes you to fall asleep with quetiapine. In any case, if you don't fall asleep within 40 minutes, you could increase the dose a little. That's what I'm thinking right now.