It's best to try natural remedies -- like eating plenty of small bland meals throughout the day, sucking on ginger candy, or drinking peppermint tea -- before turning to medication to ease your symptoms. But if nothing else seems to help, you certainly don't have to suffer.
Many pregnant women use medication to manage their morning sickness, especially if the nausea and vomiting are making it tough to work or get through the day. Your doctor may also put you on medication if you're so sick that you're losing too much weight or if he or she suspects you have hyperemesis gravidarum. Women with this more serious, but very rare, kind of morning sickness literally can't keep anything down, including water, prenatal vitamins, or medication. (Some women with hyperemesis gravidarum end up in the hospital, but they usually go on to have healthy babies.)
The two most popular drugs used to treat morning sickness are Zofran and Reglan, and they require a prescription from your doctor. However, they can be costly (not all insurance companies cover them) and don't work for every woman. When taken regularly, vitamin B6 has been shown to relieve nausea, but ask your doctor for the proper dose, as taking too much can cause numbness or nerve damage and may harm your baby.
If nausea and vomiting keep you up at night (since morning sickness doesn't just happen in the morning), consider over-the-counter antihistamines or Unisom Nighttime Sleep-Aid to help soothe symptoms, both of which may help your stomach and make you sleep better. But as with any medication, make sure to check with your doctor before taking anything during pregnancy.