nausea/vomiting
"I was first given this medication after being admitted to the ER with a kidney infection, it is a literal miracle.  I have an intense phobia of vomiting which gives me horrible anxiety anytime I feel nauseous (which is often with acid reflux and IBS) which makes the entire situation so much worse, but promethazine is an almost instant life saver.  It did make me drowsy when I first started taking it, but that has lessened as time has gone by.  It does take a while to completely work (30-60 mins depending on how amped up I am from anxiety) but as soon as I take it I know it's going to help and I am able to calm down and let it go to work.  I can't imagine going back to a life where I missed out on work and events because of nausea."