Motion Sickness

What is Motion Sickness?

  • Motion sickness (kinetosis) is the experience of unpleasant symptoms, predominantly nausea, during real or perceived motion.
  • It is most commonly observed in boat travel (seasickness), although any type of travel or motion can induce motion sickness.
  • Other examples of motion or travel sickness include car sickness and air sickness.
  • Motion sickness is considered to be a form of dizziness and can be induced in most normal individuals. It is not considered to be a specific disease state.
  • Although motion sickness can be uncomfortable, it is typically not a sign of a serious problem unless prolonged vomiting leads to dehydration or electrolyte abnormalities.

Motion Sickness Causes

The cause of motion sickness is complex and not fully understood, but most experts believe that it arises due to conflicts in sensory input to the brain. The brain senses motion through different signaling pathways from the inner ear (sensing motion, acceleration, and gravity), the eyes (vision), and the deeper tissues of the body (proprioceptors). When the body moves involuntarily, such as when riding in a vehicle, there may be conflict among these different types of sensory input to the brain. The sensory apparatus in the inner ear seems to be most critical in the development of motion sickness.

Studies have shown that some people are more likely than others to experience motion sickness.

  • Women are more sensitive to motion sickness than men, and pregnant women are especially at risk for motion sickness.
  • Children are commonly affected. The peak incidence for the development of motion sickness is 12 years; infants and children under two are generally not affected.
  • Persons who suffer from migraine headaches or conditions that interfere with sensory input (such as labyrinthitis) are at increased risk for motion sickness.

Motion Sickness Symptoms

Motion sickness can occur during any type of movement that is unintentional. Car sickness, seasickness, and air sickness are examples of motion sickness. Complex types of movement, especially slow movement or movement in two different directions (such as up and down plus back and forth) at the same time (commonly the movements of a boat in rough water) are most likely to cause motion sickness.

The primary symptom of motion sickness is nausea. Vomiting and dizziness may also occur. Other common signs are sweating, increased salivation, and a general feeling of discomfort and not feeling well (malaise).

The severity of motion sickness can vary widely, even in the same individual on different days. In the majority of cases, the symptoms stop when the motion stops, although some people may experience symptoms for up to a few days after an episode of motion sickness.

When to Seek Medical Care for Motion Sickness

In most cases, motion sickness can be treated without a visit to the doctor. But if an individual has worsening or extremely severe motion sickness, it is advisable to consult with a health care practitioner, especially if a person has prolonged vomiting.

Motion Sickness Exams and Tests

There are no diagnostic tests for motion sickness; the diagnosis is made by the characteristic symptoms appearing during travel or during any form of passive motion.

Motion Sickness Treatment

A number of different treatments have been successfully used to manage the symptoms of motion sickness and are described below.

Home Remedies for Motion Sickness

Some people who have had multiple and severe experiences with motion sickness have been helped by physical therapy that uses recurrent head movements and visual cues to replicate the environment that induced sickness, but this is not a common form of treatment. This is based upon the principle that habituation to certain movements and motions (getting accustomed to the type of motion) can occur, leading to a decrease in motion sickness over time when repeatedly exposed to the same movements.

Clinical trials have yielded mixed results concerning the value of acupressure (pressure at the P6 acupressure point on the anterior wrist, located three fingerbreadths proximal to the proximal wrist fold). Manual pressure or pressure using a bracelet or wrist band has been reported to be effective for motion sickness in some studies, but other studies have failed to show a benefit.

Due to the characteristics of the vestibular system, the brain senses motion in a frame of reference centered upon the earth rather than on the individual. Therefore, keeping the eyes fixed upon the horizon or land while on a ship or boat can reduce motion sickness. Likewise, when in a car, individuals prone to motion sickness should sit in the front seat and gaze out the window rather than looking at a book, map, or computer.

Taking 1-2 grams of ginger orally has been used as an alternative medicine to prevent motion sickness. Studies both in experimental motion sickness and in naval cadets at sea have found that ginger, taken in advance, has reduced the symptoms of motion sickness. It is believed, however, that this benefit is due to the effects of ginger on gastric (stomach) motility rather than suppression of sensory input.

Medical Treatment for Motion Sickness

Medications can be used that suppress the conflicting sensory input to the brain or help alleviate the symptoms of motion sickness. A number of different classes of medications have been effective in treating motion sickness (see below). Medications are most effective when taken in anticipation of the involuntary motion; they are less effective for symptom relief after the motion has begun.

Motion Sickness Medications

Antihistamines

Antihistamines have been used to treat motions sickness. Notably, the nonsedating antihistamines do not seem to be effective for motion sickness treatment.

Examples of antihistamine medications to treat motion sickness include:

Side effects may include significant sedation, drowsiness, dry mouth, blurred vision, and confusion and urinary retention in the elderly.

Anticholinergics

Scopolamine (Transderm-Scop) is the most well-known medication in this category. It has been shown in clinical trials to be effective at preventing motion sickness. Scopolamine is most commonly administered as a patch applied to the skin. Side effects are the same as those of the antihistamines (sedation, blurred vision, dry mouth, and confusion and urinary retention in the elderly). Persons at risk for angle-closure glaucoma should not take scopolamine.

Antidopaminergics

Two drugs in this category that have been successfully used in the management of motion sickness include promethazine (Phenergan, Pentazine) and metoclopramide (Reglan). Both of these medications can also cause significant sedation and in a few people, movement disorders (for example, torticollis or twisting of the neck, tongue protrusion).

Other Motion Sickness Medications

Ephedrine and some amphetamines have been used both to treat motion sickness and to counteract the sedating effects of other medical treatments. Studies have also shown a beneficial effect of caffeine when administered in combination with other medications for motion sickness.

Benzodiazepines have also been useful for some people with motion sickness. Examples include:

Antiemetic (anti-nausea) medications have been used to control nausea and vomiting after motion sickness has developed. Examples include:

Motion Sickness Follow-up

Motion sickness typically resolves after the motion has stopped and requires no follow-up care. In uncommon cases, symptoms may persist up to a few days following the precipitating activity. If an individual has symptoms of motion sickness that persists or worsens over time, a visit to a health care practitioner is recommended.

Motion Sickness Prevention

Any medications to prevent motion sickness (see above) should be taken prior to travel or movement. Other techniques described above, such as acupressure and fixing one's gaze upon landmarks or the horizon may help to prevent or lessen the symptoms of motion sickness.

Motion Sickness Outlook

As discussed previously, motion sickness is not a specific disease state and resolves on its own, typically when the motion has stopped. There are no long-term complications of the condition. However, prolonged vomiting can lead to dehydration and electrolyte abnormalities, which if left untreated, may lead to more serious problems such as low blood pressure (hypotension), syncope (fainting), or cardiac arrhythmias.

Sources: References

Patient Comments & Reviews

  • Motion Sickness - Symptoms

    What were the symptoms of your motion sickness?

    Post View 2 Comments
  • Motion Sickness - Treatment

    What was the treatment for your motion sickness?

    Post View 1 Comment
  • Motion Sickness - Experience

    Please describe your experience with motion sickness.

    Post
CONTINUE SCROLLING FOR RELATED ARTICLE

Health Solutions From Our Sponsors