Seasickness Prevention and Treatment

By Domenic A. Sammarco, R.Ph., EMT

What can you do to prevent or control seasickness when out on the ocean?

Recognize: The key to effective prevention is to recognize and react to your earliest symptoms. Each person’s pattern of symptom onset is somewhat different, but it is usually repeatable. Generally the first symptoms are yawning and drowsiness, then abnormal fatigue and lethargy, but if you already are tired from standing watch these symptoms can go unrecognized. For many people, the first obvious symptoms can go unrecognized. For many people, the first obvious are stomach awareness (which turns to nausea) and slight sweating.
As symptoms advance, stomach awareness turns to nausea, the face becomes pale, particularly around the nose and mouth, and hands and face become cold and clammy. Belching, salivating and flatulence are common. Concentration on mental tasks becomes difficult. Eventually nausea comes in waves, and increases in uncontrolled crescendo leading almost inevitably to vomiting. Subsequent attacks of vomiting typically develop with less warning than the first.

React: As soon as you notice you have symptoms, do something about it! Take an anti-motion sickness medication, if you haven’t done so already. Go on deck to eliminate visual conflict, and stay amidships or aft where the total motion stimulus due to pitching and rolling is less severe. Use a technique called horizon viewing: Station yourself where you have a good, broad view of the motion. You needn’t try to stare steadfastly at the horizon. It is fine to look around. If you’re an experienced helmsman, take the wheel and steer by reference to oncoming waves, the horizon, clouds and distant sails.

Ride The Waves: Don’t sit or lie inert in the cockpit, leaning against the cabin or coaming, passively letting the motion toss you around. Postural anticipation of the boat’s motion is the natural cure for seasickness. Use a method called riding: Sit upright, let your trunk and neck muscles keep your head and upper body balanced over your hips as the boat moves. Once you get the rhythm, it is far less tiring than fighting to hang on. If you feel well enough, stand up, walk around and develop your sea legs while you find some work to do.
Communicate: Let the skipper know that you have symptoms. Don’t be embarrassed, experienced skippers know seasickness happens because most get seasick sometimes themselves. They know that even a small course change can change the amplitude and frequency of the boat’s motion in the waves, often with miraculous results.

Go On Deck: To avoid visual conflicts, minimize the time you spend below, particularly if you are beginning to feel queasy. When you awaken for your watch, dress quickly and get on deck. You may feel fine wake up, but symptoms may appear once your balance brain is put back to work. Wear clothing that is absorbent, easily ventilated and quickly removed (e.g. zipper fund instead of a pullover foul weather top). Err on the side of overdressing. It is easier to remove excess clothing on deck and hand it below than to go below yourself while sick. If necessary eat on deck. When you go off watch, change and get into your bunk promptly. You won’t adapt to the motion lying down, but you will be much less susceptible. Choose a narrow berth or arrange soft duffels and sail bags around so you are wedged in and can relax completely. If you have to hang on while in your berth, your subconscious balance brain won’t easily go "off watch". Close your eyes and go to sleep. Sleeping seems largely to turn off the balance brain, allowing the emetic brain to recover.

Pace Yourself: If your duties require you to work below, remember that you often keep your symptoms under control if you can pace yourself properly with intervals of horizon viewing. Take a break every few minutes, go on deck, or stand in a hatch or look out a large cabin window. Peeking out a porthole won’t work, the idea being to obtain a wide view of the horizon in your peripheral vision. Remember that when symptoms are minimal, the delay between what you are doing and how you are feeling can be several minutes. Be alert to changes in your symptoms. With experience, you’ll usually be able to keep you nausea below the point of no return.

Think Ahead: Seasickness is the curse of cooks and navigators. Advance preparations and technology can really help. Knowing exactly where your food is stowed, moving items in calm weather from deep stowage up forward to a handy spot aft near the galley and "cooking ahead" using refrigeration have saved many a sea cook’s stomach. Prolonged reading and writing inherent in offshore navigation can be quite provocative. Consider switching to a calculator rather than using tables when working celestial sights in a seaway.

Avoid Alcohol: Drink alcohol only in moderation. Alcohol has a direct effect on your vestibular system and depending on the degree of consumption you may be made to feel dizzy anytime you or the boat moves, especially with overindulgence. If you’re hung over on the morning of departure from the previous evening’s social events, chance are good that you will donate your breakfast to Neptune.

Eat Moderately: There isn’t much strong scientific evidence indicating that susceptibility to seasickness is influenced by eating or avoiding certain foods, even though this idea is mentioned frequently in older textbooks. Feel free to eat moderate amount of whatever foods you find appealing. Diet becomes important only if vomiting occurs.

Replace Nutrients: Sometime a case of seasickness is limited to a single episode of vomiting. However, particularly in heavy weather, repeated attacks of vomiting and retching ("dry heaves") are common. Vomiting brings temporary relief from nausea, but after several episodes, weaknesses, drowsiness and apathy typically result. Sufferers usually are able to respond physically to real emergencies for a day or so. However, if you vomit repeatedly and don’t eat because you feel nauseous, eventually you will "hit the wall" and become weak, confused and eventually incapacitated. Your breath will smell like acetone. To prevent this, force yourself to eat and drink (broth, saltines and candy, for instance) frequently in small amounts. It won’t all stay down, but your net loss of fluid, glucose and electrolyte due to vomiting will be much reduced.

Observe Others: Watch leaders should be alert for weaknesses, extreme drowsiness and confusion in those suffering from prolonged seasickness. Severely afflicted crewmembers are often reluctant to go below because they might feel worse and they don’t want to leave the rest of their watch shorthanded. Instead, they linger on deck, sometimes even falling asleep at the leeward rail. Seasick crewmembers easily can fall or be washed overboard. Insist that they use harnesses. Don’t permit them to remain on deck under storm conditions. They are more likely to be able to respond in a real emergency if you get them wedged in a berth down below, medicated, fed and resting.

Have A Plan: When preparing for a trip, the skipper or "ship’s doc" should develop a plan for management of seasickness cases in advance. Find out what anti-seasickness drugs each crewmember plans to use and keep them all in a dry place very handy to the deck, not in a medicine locker located in the lurching, smelly confines of the head. Make sure you know whether any crewmembers have preexisting medical conditions such as ulcers or diabetes, or require special medications. These people may develop additional problems if they suffer from severe seasickness. Work out a viable plan for treating them.

Before departure, review procedures for prevention and treatment with your entire crew. Designation a narrow sea berth aft for use by the afflicted and have a supply of emesis bags, disposable towels, easily opened juice or water bottles and candy available in the bunk. Bags really are far superior to the traditional bucket. Airline bags are adequate, but even are the inexpensive "sic sacs" available at aviation stores. These are much easier to use in a motion environment even when lying down.

Consider the Raft: Be certain your life raft medical kit is well stocked with anti-motion sickness drugs. Rafts have a really jerky motion and the canopy on the raft—although it provides essential protection from the elements—deprives the occupation of outside visual references. Because of this, seasickness in rafts is common

Medications: Anti-motion sickness drugs are a very effective way of raising your threshold for seasickness and of hastening recovery if you do become sick. As shown in the accompanying table, a wide variety of useful drugs is available. The problem is that many sailors are reluctant to use them, usually because of concerns about side effects (e.g. drowsiness and blurred vision). Also, all oral drugs require at least a half-hour, usually more, to become effective. Many people try drugs but give up on them, simply because they failed to take them in time. Finding a drug that works for you is worthwhile. Before choosing or using any anti-motion sickness drug, consult with your own physician or pharmacist, someone who knows your medical history, who can prescribe the stronger drugs and suppositories and who can advise on the type and dosage you can take safely. Not all anti-motion sickness drugs are appropriate for use by children. Women who are, or might be, pregnant should avoid drugs entirely.

If you are relatively susceptible to seasickness, or haven’t sailed offshore recently, prophylactic drug use is probably the best strategy. To find one with acceptable side effects, experiment with several different types ashore first, taking them on the same schedule you would use at sea. When choosing a drug, duration of action is an important consideration, because bad weather offshore can last for several days and you must take doses at regular intervals. Longer acting drugs—such as meclizine, promethazine, cinnarizine or dimenhydrinate in time-release form—thus have practical advantages.

One prescription drug of interest to sailors is an adhesive patch worn behind the ear, which continuously administers a dose of the drug scopolamine through the skin over a three-day period. The idea is to try to minimize the incidence of side effects by maintaining a relatively constant level of scopolamine in the blood. The patch has been sold in the United States as Transderm-Scop only by prescription, but it has been available without one in Bermuda and in many provinces in Canada. It was taken off the market due to production problems, but at press time the manufacturer expected to make the patch available by late 1996.

NASA astronauts now generally avoid oral and transdermal premedication and rely on intramuscular injection of promethazine for treatment. The injections leave a painful sore spot and may make you very sleepy. But when combined with bed rest, injected promethazine can give fast and effective relief, and the dose is not lost if the person vomits again. Use of injectables may make good sense when sailing offshore, but you must have a person aboard who is properly qualified to prescribe and administer them. A more practiced, but slower-acting alternative is the rectal suppository. However, remember that suppositories, too, require a prescription (in the United States) and can become difficult to use unless stored in a cool place.

Biofeedback/Relaxation: Using biofeedback, progressive and/or autogenic imagery, many people can learn to control volionally, to a degree, their own heart rate, blood pressure and skin temperature if they practical regularly. Because the emetic brain is closely coupled to centers controlling these functions, there is reason to hope that these same methods can be used actively to suppress symptoms of motion sickness. You may have heard that several NASA and Air Force psychologists have experimented with this approach, which avoids the side-effect problems associated with anti-motion-sickness drug use. Results have been encouraging, but the studies have been small scale and have been done mostly by advocates. Despite 20 years of research, the approach has not been adopted for regular use by NASA or the U.S. military.

Finally… The moral of this story is that you can do a great deal to prevent and treat seasickness when you know its causes. Coupling of the balance brain to the emetic brain is a universal human response to any abnormal motion environment. Susceptibility only disappears when your balance brain learns to anticipate subconsciously the next wave. Drugs can be of real value until you adapt. So too can techniques such as wave riding and horizon viewing, provided you recognize and react to your earliest symptoms. If you do become severely sick, there are importantly thing you can do to make the experience less unpleasant and to assure a prompt recovery. Over the long term, the best way to prevent seasickness, aside from staying ashore, happens to be the most enjoyable: Go sailing a lot.

Useful Anti-Motion Sickness Drugs

Generic Name
Brand Name  (Manufacturer)
Duration of Action
Dramamine   (Searle)
tablet (OTC)
liquid (OTC)
injection (Rx)
4-6 hr
4-6 hr
4-6 hr
Dramamine  (Richardson)
chewable tablet (OTC) 4-6 hr
Gravol (Horner)
capsule (OTC:B&C)
suppository (OTC: B&C)

6 hr
6 hr
Meclizine HC1
Bonine  (Leeming)
chewable tablet (OTC) 6-12 hr
Meclizine HC1
Antivert  (Roerig)
tablet (Rx) 6-12 hr
Meclizine HC1
Meclizine  (Geneva)
tablet (OTC) 6-12 hr
Stugeron  (Janssen)
tablet (Rx: UK&B) 6-12 hr
Marezine  (Burrough)
capsule (OTC)
4-6 hr
4-6 hr
Transdermal Scopolamine
Transderm-Scop (CIBA)
skin patch (Rx, OTC: B&C) 2-3 days
Phynergan  (Wyeth)
tablet (Rx)
suppository (Rx)
injection (Rx)
6-12 hr
6-12 hr
6-12 hr
Promethazine & Ephedrine
Phernergan + Ephedrine (Wyeth)
tablet (Rx) 6-12 hr
OTC: over the counter
Rx: by prescription only
OTC (B&C): OTC in Bermuda & Canada
OTC (UK&B): OTC in UK & Bermuda