I keep promethazine on hand for nausea. It works well on me and I make sure my Dr keeps me supplied with it lol. When I start having a ton of pain I get really nauseous and nothing usually works, except the promethazine, also called fenergen. Even peppermint doesn't deal with my nausea, and when I start vomiting just leave me be with a big glas of water and a stool to sit on. But then again rsd is different for all of us except the pain.