Motion sickness, as many travelers know all too well, can strike on ships, trains, planes or in a car — whenever the balance center in the inner ear senses motion that the eyes do not. Those mixed signals, which are sent to the brain, can literally be sickening.

So, if you’re prone to motion sickness, don’t even think about reading on a winding road or on a bumpy flight; the words on the page are still, but your inner ear senses movement. The result can be nausea, dizziness, clammy hands and, alas, vomiting.

The most common advice for avoiding carsickness and seasickness is to look at the horizon, as that reference point makes it clear you’re moving. On a ship, it may be a good idea to stay out on deck where you can keep your eyes on the horizon. In a car, it helps to drive or sit in the front seat since you can see farther ahead than from the back seat. On a plane, try to book a seat near the wings, where it is more stable.

The youngest among us are thought to be the most susceptible to motion sickness, though it’s not known why. Children who can barely see out of a car window pose a special challenge for parents, since they are doomed to the back seat. (Even puppies are more susceptible than adult dogs; panting, drooling and dilated pupils are all signs of motion sickness in animals.)

A few tricks will help smooth the car ride for young and old, human and canine: Stick to highways rather than stop-and-go routes or snaky back roads, and consider getting new shock absorbers, if needed, to minimize bounce. Cooler temperatures might also help, said Joseph M. Furman, a professor of otolaryngology and neurology at University of Pittsburgh Medical Center, who used to drive with the windows cracked in winter to soothe his son. If his daughter asked why, he would say, “Do you want your brother to puke or do you want to put on a coat?”

The best way to avoid motion sickness is, obviously, to avoid travel. But planning can help make it more bearable. Below are suggestions from experts on how to combat motion sickness, especially in cars, and with special attention to children.

THE TECHNOLOGY FIX

These days, children are often pacified with their 67th viewing of Toy Story 3. But the jury is out as to whether movie-watching en route will only make them more squeamish. Anne Mounsey, an associate professor of family medicine at the University of North Carolina in Chapel Hill, tells parents any screen activity requires “trial and error.”

Children, or passengers of any age, who are only mildly sickened en route might do fine watching a fixed screen like a DVD player in a minivan. But a tablet that must be held steady? Not a great idea. Similarly, a hand-held game console provides too much visual stimulation at close range.

Children or adults can listen to an iPod instead, with their heads on the headrests for stability, eyes closed to limit stimuli.

And in this age of nonstop engagement with personal technology, a recommendation from Dr. Abinash Virk, the director of the travel and tropical medicine clinic at Mayo Clinic, in Rochester, Minn., is refreshing. “Spacing out is great,” Virk said. “Your brain is having to deal with input from ears and eyes. The more you try to do the more likely you’ll get nauseated.”

THE MEDICATION FIX

Several drugs can be useful. A prescription-only scopolamine patch — worn behind an ear — reduces nausea associated with motion sickness, studies have shown. But its side effects include dry mouth and blurred vision. That said, the patch lasts three days, making it convenient for the seasick-prone on a Caribbean cruise. However, children under 18 should not use a scopolamine patch as it can cause “terrible toxicity,” said Dr. Sydney Spiesel, a clinical professor of pediatrics at Yale University School of Medicine. It should also not be used by anyone who has or has had glaucoma.