Packing for a two-week trip through the Arctic on a nuclear icebreaking ship sounds like an extraordinary endeavor, but it's all part of the job for Dr. Joanne Feldman, Assistant Clinical Professor at UCLA's Department of Emergency Medicine and a polar expedition physician with Quark Expeditions. Dr. Feldman, better known as Dr. Jo, has become an expert in motion sickness treatment through many seasons of braving the high seas on expedition ships to both the Arctic and Antarctic; and her specialty in wilderness emergency medicine and experience as a physician with the U.S. Antarctic Program at Palmer Station primed her for the challenges of experiencing life at the extremes. For the less seasoned on the seas, Dr. Jo is a resource as well as a potentially lifesaving presence. Condé Nast Traveler spoke with her onboard the ship 50 Years of Victory as it powered through ice near the North Pole:
Let’s say a traveler is going on their first boat vacation—a cruise or an expedition trip—and they’re worried about having motion sickness. Should they take Dramamine? Is that the “go to” for a first-timer?
For most people, Dramamine works if the seas aren’t big. Dramamine has two different formularies. One is meclizine and one is dimenhydrinate, which is Benadryl plus a stimulant. One is drowsy and the other is non-drowsy; that’s how they come off, but the same name, “Dramamine,” is used in the two different formulations.
So if someone is leaving on a last-minute trip, could they just grab Benadryl in a pinch?
Supposedly they can, although it’s not as effective. I think that if you’re in a pinch and you have nothing else, then I would do it. You want to use an antihistamine, and I’m going to go into detail because this is cool to know.
The reason we get seasick is because we’re getting different information going to our brain, and our brain doesn’t know what to do. The way I know I’m moving on a ship is three ways. One is visually: from looking out a window I can see that I’m moving. Two is [that] my inner ears with the semicircular canals tell us that we’re moving, and it’s sending signals to the brain. And three is proprioception: my butt right now, or my feet when I’m standing. You know you’re moving because all of a sudden you have more pressure on one side...and then more pressure on the other.
The problem when we’re seasick is our brain gets confused, because if I’m inside and I can’t see that we’re moving, my inner ear tells me I’m moving but my eyes tell me I’m not moving, and my proprioception tells me I am moving. So there’s a conflict between the eye and the inner ear and, as a result, our body gets confused and that’s what seasickness is. We get nauseated, or we sometimes feel a spinning sensation. By knocking out the information coming from our inner ear...for some reason that overrules everything else and that is how the medications work. It gets rid of the stimulus coming from your inner ear. It’s the same thing with vertigo. When people get vertiginous, we give them an antihistamine like meclizine too, for that.
There are two little receptors that the stimulus...you know, the little neurotransmitter goes in and then sends the signal to the brain. In our inner ear they are histamine receptors, so antihistamines work. And then muscarinic receptors, and scopolamine blocks that one, so we either use antihistamines or antimuscarinics. So that’s why scopolamine is used, or the antihistamines, and the best ones are promethazine, which is my favorite; meclizine; and then there’s a list of others...they end with “ine.”
So promethazine is your favorite, but that’s prescription-only in the U.S., right?
In the U.S., yes. Currently in the U.S. you have to tell your doctor, “Hey, can you write me a prescription?” because a lot of doctors do not know this is actually used for seasickness. It’s been used forever for anti-nausea but now that we’ve got Zofran, which is ondansetron, everyone uses that. A lot of people don’t use promethazine anymore for anti-nausea, and a lot of doctors don’t know that that is the best anti-seasickness medication. That’s what [NASA] uses for space sickness, which is supposedly worse. The downside is that it’s more sedating than any of the other ones, but I’d rather be tired instead of being tired from being seasick and vomiting at the same time and feeling like crap. And what they do for astronauts—I’ve actually talked to the doctor who was first to give a shot of promethazine in space, on the Space Shuttle—is they mix it with caffeine. We don’t carry caffeine. I just tell people to go drink a lot of caffeine.
So if you’re crossing the Drake Passage and if you want “the bomb,” I carry tons of [promethazine]—like I have a bottle of one thousand here—is use this because I think that’s the best. Promethazine. But If I’m like, “I’m just going to cross on a ship for an hour and there’s going to be waves but it’s only an hour and it’s not too bad, not big waves," then I’ll just use meclizine because it’s a little less sedating.