Mariners Memos


Health maintenance and safety at sea requires four "ships:" A seaworthy mother ship, competent seamanship, experienced leadership, and dedicated "selfmanship." Selfmanship is the art and practice of caring for one's self (and the crew) at sea. The considerations for managing selfmanship are what Dr. Peter Goth calls The Fearsome Five: Fluids, Food, Fahrenheit, Fatigue, and Fitness. A problem with any of these will result in impaired physical and mental performance. To remain healthy at sea, one requires sufficient fuel in the form of healthy food to maintain energy and normal body functions, adequate amounts of clean drinking fluids to prevent dehydration, protection from the elements (sun, wind, water, spray, cold, and heat) to maintain normal body temperature (Fahrenheit), sufficient time to nap, sleep or rest in order to overcome fatigue, and an environment conducive to maintaining personal fitness to prevent injury and illness. This guide addresses many of these issues. Focus on the fearsome five before you leave and during your trip, and you should remain well and return in good, if not better health.


Seasickness results from a mismatch of sensory input processed by the brain to orient the body's position. Inside the cabin of a rolling boat, the eyes detect no tilt, but fluid in the inner ear shifts with the boat's motion, sending a different position signal to the brain. Sensors in the neck, muscles, and joints relay additional information depending on how the person moves and maintains balance. The conflict of sensory data from all these areas ultimately activates a series of responses, including nausea and vomiting.

Untreated, seasickness leads to rapid physical and mental deterioration, posing a major hazard to crew health, safety, and morale. It may take as long as three days to adapt to the boat's motion and get one's "sea legs." Medication and a variety of tactics are more effective in preventing symptoms than reversing them during this period of adaptation.

Start the trip well hydrated, and avoid alcohol. The night before, begin medication such as Bonine®, Dramamine®, or Phenergan®. Repeat doses at the recommended intervals. Several hours before departure, eat a light meal low in fat and high in starch. Sudafed®, Nodoz®, or ephedrine will counteract the drowsiness caused by medication. The prescription Transderm-Scop® adhesive patch, applied behind the ear two hours before departure, may cause less fatigue and is effective for three days. Scopace tablets allow sailors to regulate the amount of Scopolamine to reduce side effects.

Alternative therapies, which may be beneficial, include ginger capsules, one gram every six to eight hours, supplemented with ginger snaps, candied ginger and ginger ale. The Reliefband® is a wristwatch-like device which delivers electrical stimulation to nerves in this same area (the P6 acupuncture site).When positioned properly, the wearer will feel a pulsed tingling sensation across the palm and in the middle two fingers. An elastic band with a plastic stud that applies pressure to the same acupuncture site without electrical stimulation may also be effective for some boaters. A variety of medications, devices, procedures, and herbal remedies work for some people and not others. If you have discovered a safe system that works for you, stick with it and believe in what you use.

After departure, limit the time spent below decks. Set up dive gear at the dock, and avoid close-focused visual tasks such as reading or navigating. Stay out in the fresh air, near the center of the boat where the motion is less severe. Munch on crackers and sip water or juice. Keep your eye on the horizon to provide a stable reference point; sit or stand upright with head and upper body balanced over the hips, and anticipate the boat’s motion as though riding the waves.

Signs and Symptoms
The earliest signs and symptoms are yawning and drowsiness, progressing to dry mouth, headache, dizziness, and extreme listlessness. Some people initially experience an unsettled stomach, slight sweating, mild blushing, and a feeling of warmth. Later the face becomes pale, cold, and clammy. Nausea comes in waves with belching, salivation, and uncontrollable vomiting. Begin immediate treatment with anti-nausea medication.

When symptoms progress, lie down and try to sleep. Take small amounts of fluid, crackers, and hard candy. Phenergan® taken as a pill, but preferably as suppository or injection, will prevent additional vomiting and dehydration. Repeat every six hours as needed and treat for dehydration.

Scuba divers risk seasickness when boating to the dive site. Don't dive if you're nauseated and vomiting. Underwater, this can lead to panic, rapid ascent, aspiration, or drowning. Milder symptoms may be treated by quickly getting off the dive boat into the water and holding on to a safety line at the surface for five or ten minutes. Drugs that cause drowsiness also increase susceptibly to nitrogen narcosis. Divers should therefore experiment with different seasickness medications well in advance of a planned dive trip to find the least sedating, most effective drug.

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