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June 2001 Vol. 16, No. 6   RSS Feed for Undercurrent Issues
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Seasickness Preventive

from the June, 2001 issue of Undercurrent   Subscribe Now

To the Editor,

Your recent article about seasickness prevention made some good points. Dramamine and Bonine (antihistamine class) make most people too drowsy to be useful.

Scopolamine patches (anticholinergic class) are effective, especially for extended use. However, they, too, have some troublesome side effects including: dry mouth, sedation, difficulty focusing, disorientation, and in severe cases, psychosis. Also, the drug requires a prescription and needs to be applied 3-4 hours ahead of time to be effective.

A few years ago when scop patches were unavailable, I discovered a great drug, Marezine (cyclizine hydrochloride). It is in the same class (antihistamine) as Dramamine but it’s much less sedating. You only need to take it one hour ahead of time to be effective and it lasts for 4-6 hours — perfect for day trips. A bottle of 100 tablets costs about $50.


Larry Hardy, M.D.
Houston, Texas

Thanks for the tip. The latest research on transdermal scop is that it takes effect only 6-8 hours after application. Furthermore, 22 percent of the subjects had not achieved therapeutic levels of scopolamine as long as 8-9 hours after drug application, which may explain why up to 30 percent of the people don’t think it works.

Researchers (see below) have found that people taking Dramamine (dimenhydrinate) at 66 fsw had a significant decrease in mental flexibility scores and could have serious consequences on a diver’s mental functioning and judgment.

Marezine has proven to be effective in comparison to Dramamine; however, we’re not aware of tests under pressure. Although it has been tested at sea level pressure 30 minutes after ingestion, drowsiness was significantly higher with Dramamine than with Marezine. But after being subjected to severe motion, those taking Marezine were significantly more drowsy.

Marezine was more effective than Dramamine at reducing subjective symptoms of motion sickness. Central nervous system symptoms were slightly higher following Marezine ingestion. And treatment with Marezine resulted in significantly fewer gastrointestinal symptoms. The authors concluded that Marezine, which has a direct effect on the stomach, is more effective in preventing motion sickness gastric discomfort, whereas Dramamine, which works through its sedative properties, is more effective in preventing central nervous system symptoms of motion sickness.

Weinstein, S.E., Stern, R.M., “Comparison of Marezine and Dramamine in Preventing Symptoms of Motion Sickness,” Aviation, Space, and Environmental Medicine, Vol. 68, No. 10; 890-894, October 1997.

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