Seasickness is a form of motion sickness characterized by a feeling of nausea and, in extreme cases, vertigo experienced after spending time on a craft on water. It is typically brought on by the rocking motion of the craft. Some people who’re particularly vulnerable to the condition feel seasick simply by setting foot on a boat, even if the vessel is in dry dock. Then again, there are others who’re relatively immune, or become immune through exposure.
Seasickness is a potentially debilitating condition that can prove to be fatal if the sufferer has an important seafaring role to carry out, such as steering a yacht through stormy seas while avoiding rocks and other hazards. It’s also particularly hazardous for scuba divers who, through dehydration following vomiting, are at increased risk of decompression illness.
Treatment of Seasickness
- 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’s usually repeatable. Generally, the first symptoms are yawning and drowsiness, then abnormal fatigue and lethargy, but if you are already tired from standing watch, these symptoms can go unrecognized. For many people, the first symptoms can go unrecognized, so the first truly obvious signs of this condition are stomach awareness (which turns to nausea) and slight sweating.
- 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’s 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 while 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’s 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’re beginning to feel queasy. Sleep on the bunk during given rest periods. When you awaken for your watch, dress quickly and get on deck. You may feel fine waking up, but symptoms may reappear once your inner balance 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’s 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 duffel and sail bags around so you’re wedged in and can relax completely.
- 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.
- Think Ahead: Seasickness is the curse of cooks and navigators. As such, advance preparations and technology can really help. Knowing exactly where your food is stowed, moving items in calm weather from deep storage up forward to a handy spot aft near the galley and “cooking ahead” using refrigeration have saved many a sea cook’s stomach.
- 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 amounts 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.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.
- 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 crew member 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 crew members 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 as well.
- 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. A wide variety of useful drugs is available for this malady. 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. Ergo, 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 you 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.
- 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 effects 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.
As such, now that you know most everything you need to know about treating and handling seasickness, your seafaring days should be safe and clean. 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 your nausea below the point of no return.