This is a condition in which a discrepancy exists between visually perceived movement and the vestibular system's (a system located in one's inner ear) sense of movement. It can be manifested as airsickness, car sickness, or, the most common one, and seasickness.
When feeling motion but not seeing it (as in a ship with no windows), the inner ear transmits to the brain that it has the impression of motion, but the eyes tell the brain that everything is still. As a result of the disagreement, the brain may deduce that one of them is hallucinating and that the hallucination is due to poison ingestion. It responds by inducing vomiting, to clear the supposed toxin.
The usual symptoms of this state are exhaustion, dizziness and nausea (which generally leads to vomiting, especially when it comes to seasickness).
Preventing travel sickness
There are a few tricks that might help one prevent a frequently occurring travel sickness. For instance, breathing fresh air or closing one’s eyes and trying to sleep are rather effective. Furthermore, one should avoid drinking alcohol or heavy meals before travelling. Then, one should not read a book or watch a movie (this has been shown to be counterproductive), rather look ahead at a fixed place on the horizon.
This type of treatment has many upsides. It is completely natural, has no side-effects and treats the symptoms in a very short time.Nux Vomica. If one is feeling an severe headache followed by retching (often with nothing coming out), requires warmth and cannot bear tobacco or coffee, this is the cure that might help. Borax, when one is fearful of downward motion. Cocculus Indicus, when nausea worsens with the sight or smell of food, the person feels dizziness and needs to lie down. This is one of the most used remedies for car sickness. Also used when one is experiencing severe jet lag. Argentum Nitricum. Used when one feels chlaustrophobic, accompanied by grave sense of dizziness and nausea. Tabacum, used mainly for seasickness, when one is extremely pale or somewhat green, vomits often and is covered in cold sweat. Kali Bichromicum, also used for seasickness. When one feels pains in their bones and the dizziness an nausea feel worse when standing in an upright position. Rhus Toxicodendron, usually used for air sickness. When a person has a headache around the forehead, the mouth is dry and one is feeling an extreme amount of thirst.