By Dr Ananya Mandal, MD
Motion sickness, also termed kinetosis, is a generalized term that is used to describe an unpleasant set of symptoms like nausea, vomiting and dizziness that occurs when a person is travelling.
As the travel course progresses the symptoms may improve while the body adapts to the conditions leading to the sickness.
Motion sickness may occur while travelling on the road, by air and commonly occurs while travelling on water (sea sickness). Some individuals fail to experience a lessening of their symptoms until they stop travelling. 1-5
What causes motion sickness?
To understand the cause of motion sickness the vestibular system deep inside the ears needs to be understood. This vestibular apparatus is a set of tube like canals with a special fluid called the endolymph.
Normally movement of the head leads to movement of this fluid and stimulation of the tiny hair cells within the tubes called the membranous labyrinth. These in turn tell the brain about the position of the body and regulate the balance and posture. The eyes too send in signals to the brain regarding the position of the body.
Motion sickness occurs when there is a conflict between what the eyes see and what the inner ear detects. The brain receives a jumble of information from these inputs. This leads to dizziness, nausea and sometimes vomiting.
Motion sickness is brought about by unusual movements during travelling. This could be repeated acceleration, deceleration, going over bumps, or round in a circle.
Symptoms other than the common ones include sweating, drooling saliva, headaches, going pale etc.
Travel may not be the only reason for motion sickness. Anxiety, strong smells or even trying to read while in a moving vehicle may trigger motion sickness.
Other varieties of motion sickness include space sickness, virtual reality sickness, ski sickness, and even camel and elephant sickness.
Who is at risk of motion sickness?
Although almost everyone at some point in life may get motion sickness, some are particularly more vulnerable. Sea sickness – a form of motion sickness that affects sea farers may affect almost anyone especially if the sea is rough.
Among the rest around 3 in 10 individuals may have symptoms of motion sickness regularly on journeys by road, sea or air.
In addition women are more likely to get motion sickness than men. This is especially so if they are pregnant or are menstruating. It is speculated that hormonal changes may be responsible for this propensity.
Migraine suferrers are also more likely to suffer from motion sickness. Children between ages 2 and 12 are at a greater risk of motion sickness. Most of them grow out of the tendency as they become teenagers.
How can motion sickness be treated?
Mild symptoms of motion sickness usually can be treated by self-care methods like closing the eyes – thereby cutting down information inputs from the eyes and by distractions like listening to music. Those with more serious forms of motion sickness need therapy with medications such as Hyoscine.
Prevention of motion sickness
For prevention vulnerable individuals may ask to sit in the front of a car, over the wing of a plane, on deck in the middle of a boat. This keeps the motion to its minimum.
These individuals are advised to keep their eyes closed or sleep, avoid reading or watching a film or video, avoid looking at moving objects such as sea waves or other moving vehicles but stare at a fixed spot over the horizon and avoid heavy meals, spicy or greasy foods or alcohol before or during travel.
Reviewed by April Cashin-Garbutt, BA Hons (Cantab)