Who gets sea sickness?
Sea sickness can ruin sea voyages whether on small yachts or larger cruise ships. Although anyone can get sea sickness in severe conditions, some 20-30 % of the population are more prone, especially migraine sufferers, women and children. Situations that increase susceptibility include changes in boat motion, on-board reading, heavy weather, passenger fatigue and even extreme smells. Prevention measures are better than relying on using medications to treat sea sickness.
Causes of sea sickness
The cause of sea sickness although complex, can simply be described as an imbalance between the motion you witness and what is sensed by your middle ear motion-sensing organs (vestibular pathway). The brain senses motion via input from your eyes, skin and inner ear, and if disrupted your stability and balance can be lost. Triggers for this include stress or sensory overload and both can trigger among other things an internal release of histamine that may lead to vomiting, nausea, dizziness (vertigo), tiredness, sweating, dehydration and general discomfort. Symptoms usually improve when the movement ceases, or your body adjusts to the voyage. Symptoms can vary from very mild to so severe that people become incapacitated.
Prevention is best
Strategies for prevention of sea sickness include keeping your eyes closed, sitting face forward or looking at the horizon out a window. It is better to avoid reading, using mobile devices or watching any moving objects. Minimising head or body movements by lying down and keeping your head still is effective
Fresh air and staying calm can help, so consider listening to music or focusing on your breathing on board. Opting for more frequent lighter meals in smaller portions and avoiding alcohol and smoking all help reduce seasickness symptoms. Eating ginger or ginger flavoured lozenges has some weak evidence supporting symptom reduction, but no evidence currently exists for magnets or acupressure bands.
Medications for seasickness
If simple preventative options fail, medicines such as Hyoscine (brands include Kwells and Travacalm) taken just prior to sea travel may help but can interact with other prescription medications. Most hyoscine based medications have side effects including sedation, dizziness and dry mouth or bladder irritation, hence are not routinely recommended for children.
Older antihistamines brands such as Phenergan (not usually Claratyne/Zyrtec) taken the night prior can also help prevent sea sickness. Antihistamines can be useful for children over two years old if dosing is followed carefully. Prescription anti-nausea drug brands such as Stemetil or Zofran can be effective but often expensive. Please note Scopolamine pills or patches are not available in Australia due to side effects including hallucinations. However it may be prescribed by ship doctors or available at your end destination. You may see them worn as patches applied behind the ear and can help symptoms for up to three days. So in summary despite treatments being available, preventing sea sickness is what we all should ideally wish for.