This
page describes vertigo and dizziness rather well.
Mx7,
if this vertigo/dizziness is causing you problems in doing normal every day activities, go to your doctor and have them check you out. Vertigo is not fun, and it's probably the thing about my MS that I hate the most at this point.
There are so many different things that can cause vertigo. I still dont know exactly what was causing mine. Just because mine responded to the steroids doesnt mean that it was caused by my MS. You should go get checked out, there are probably other anti-emetic drugs they could probably give you that might not cause you too much drowsiness. Plus, if there's a treatment for it, it'll probably go away faster for you than waiting for it to go on it's own.