There are also a few things you can do to reduce sensation of motion sickness, even when it has started. 1) Move to point of least movement. Try and sit in centre of plane or in middle of boat. On boats it often helps to lie down, although it might feel like last thing you want to do. 2) Sit facing forward. 3) Look at distant scenery. 4) Get some fresh air, but keep warm. 5) Avoid talking but try not think about your motion sickness. 6) Move gently, don’t stand up or move suddenly.

Sometimes preventatives don't work, so, particularly with children in your nice clean car, it's worth being prepared. Having been car sick into my grandmother's hat at a young age, as a child I was used to travelling with a quite frankly grotesque pink potty. Whilst this would catch offending substance, it didn't contain it particularly well, meaning having to stop car to remove contents and smell.

This wasn't too difficult in 60s and 70s, but with so much traffic now it's not always easy or safe to do. Plastic shopping bags offer little help. Designed to just about hold together for trip home, they have holes in them, which prevent suffocation but reduce ability to hold liquid. Another favourite, ice cream tubs work better than pink potty, but rely on child to get lid on without spilling. Unfortunately they are wide but not very deep making spillage a distinct possibility. The best option is sick bag, as used by airlines and ferries for many years. Sick bags work brilliantly. They are simple for children to use, they are deep so reduce spillage and top can be rolled down, retaining contents and smell. Some sick bags have a clip securing rolled down top and a flat bottom, meaning they can stand up on floor of car, further reducing risk of spillage.

As companies fight to bring costs of air and ferry travel down sick bags are handed out almost on an as needed basis. The days of accumulating a stock of sick bags from an air flight seem to be over.