Parents.com just posted a really good article on how to tell if a drug is safe to take. You could try and look it up, if but I would wait until you can ask a dr.
I tried while preggo, didn't help still woke up in middle of the night and woke up groggy more than normal in the morning.
Unisom is safe to take during pregnancy-it is actually recommended in combination with B6 for nausea and vomiting! I required Reglan and Zofran around the clock so I never tried it but it's definitely safe (:
I'm like BabyBoysMama, I was prescribed all of those medications, vitamins, and Unisom to deal with hyperemesis gravidarum. None of them work, but the Unisom did help me go to sleep at night. I still woke up in the middle of the night though. However, if you decide to take Unisom, it has to be the Unisom TABS NOT THE UNISOM GELS. Above all, ask your Doctor before taking anything!