I also get motion sickness - so when we went on a boat trip in BVI - I got my doctor to write me a prescription for the Scopolamine patch which a friend of mine recommended to me. It's easy to use - just put patch behind your ear. No sleepiness. The only side affect I did have was somewhat blurred vision when trying to read (like book or computer reading). My distance vision was not affected. Here is info on it off of Yahoo Health http://health.yahoo.com/ency/healthwise/uf4450:
Scopolamine for motion sickness
A prescription drug called scopolamine may prevent symptoms of motion sickness if it is used before travel. Scopolamine is available in a patch called Transderm Scop or in a pill called Scopace. Scopolamine prevents nausea and vomiting by blocking signals from the inner ear to the brain.
You place the coin-sized Transderm Scop patch behind your ear about 4 to 8 hours before travel. It can be worn for 3 days, so it may be especially helpful for lengthy exposure to motion, such as on a cruise. You can use another patch at the end of the 3 days for longer trips.
It is important to wash your hands with soap and water after placing or removing the patch; otherwise, you might rub your eyes and get medication on them, increasing the risk of side effects such as blurred vision.
The pill Scopace should be taken on an empty stomach about 1 hour before you travel.
Scopolamine may cause side effects such as sleepiness, dry mouth, and blurred vision. Less common side effects include confusion, skin rashes, and difficulty urinating.
Those who should avoid this medication include older people, pregnant women, people who have glaucoma or difficulty urinating (such as from an enlarged prostate), or—usually in children—an obstruction of the valve (pylorus) between the stomach and the small intestine.