oops - forgot to mention also - something I've had in the hospital before and I'm not even sure if it's available in pill form or only IV form - anzimet. Works great and not sedating - at least not for me.
I also suggest phenergan if you can't afford the zofran - it really does work quite well - is quite sedating at first, but that does seem to wear off pretty quickly.
I've taken phenergan for many years for chronic nausea. The sedative effects wore off pretty quickly in about a month of regular use. Zofran is the gold standard of nausea/ vomiting management, and I believe it's now available as a generic making it an affordable option.
Reglan doesn't really work well unless the nausea is caused by slow GI motility. It works by increasing motility and speeding up stomach and intestinal transit time. Reglan is also not meant to be taken long-term, although doctors routinely prescribe it that way. In too-high doses, psychosis can occur. I've seen this reaction in one of my dogs who was taking Reglan for nausea related to kidney failure. I found one study online that was done several years ago that noted severe side effects in some people and dogs who took Reglan regularly for several months or at high doses. For the most part, it's a safe and effective medication. It's just not the most effective medication for opiate-induced nausea.
Zofran is a wonderful medication. If you can afford it, stick with zofran. Phenergan works well but it makes you super sleepy and it also increases the bad side effects of narcotics- like dizziness and light-headedness. Same with phenergan's cousin, compazine. There's reglan as well, but to me it doesn't work as well. If you are taking the opiates for short-term treatment for something like post-surgical pain, phenergan or zofran are likely to be your best options....but if you're taking them for a long time, i.e. a pain management program where you'll be on opiates for a long time, you may want to consider decreasing your dose...very often decreasing your dose a small bit will eliminate or at least lower your nausea.
Phengren is great and cheap.
Zofran is a good anti-nausea medication, however, it's very expensive. There are less expensive meds available that may help you just as much. I suggest checking with your doctor and see what he/she suggests.