Timothy C. Hain, MD Page last modified: March 1, 2009

Motion sickness is the nausea, disorientation and fatigue that can be induced by head motion. The first sign is usually pallor. Yawning, restlessness and a cold sweat forming on the upper lip or forehead often follow. As symptoms build, an upset stomach, fatigue or drowsiness may occur. The final stages are characterized by nausea and vomiting.

Motion sickness is common and normal. Nearly anyone can be made motion sick by an appropriate stimulus, except for individuals with no vestibular system (William James). In a large study done in India, the prevalence of motion sickness was about 28%, and females were more susceptible (27%) were more susceptible than males (16.8%). Individuals with more active occupations are less susceptible (Sharma, 1997). In medical transport personnel, 46% of personnel reported nausea and 65%, the sopite syndrome (sleepiness caused by motion). (Wright, 1995)

According to Benson, nearly 100% of occupants of life rafts will vomit in rough seas. 60% of student aircrew members suffer from air sickness at some time during their training. For vertical motion (heave), oscillation at a frequency of about 0.2 hz is the most provocative. Motion at 1 Hz is less than 1/10th as provocative. About 7% of seagoing passengers report vomiting during a journey (Lawther and Griffin, 1988). Women are more sensitive to motion than men, by a ratio of about 5:3, although this may be related to reporting differences rather than true physiological differences( Cheung, B. and K. Hofer , 2002)

In order for the body to determine where it is at all times, the brain combines visual information, touch information, inner ear information, and internal expectations. Under most circumstances, the senses and expectations agree. When they disagree, there is conflict, and motion sickness can occur.

For example, consider the situation when one is reading in the back seat of a car. Your eyes, fixed on the page, say that you are still. However, as the car goes over bumps and accelerates/decelerates, your ears disagree. This is why motion sickness in this situation is common.

Acquired susceptibility to motion sickness occurs occasionally. Persons with an inner ear disturbances, especially a recent one, may be intolerant to activity in general. People with migraine are apt to get motion sick. Persons with rare, central nervous system disorders of the part of the brain that processes signals from the inner ear may also be unusually susceptible to motion sickness. Certain individuals who are constitutionally susceptible to motion sickness and can develop sea sickness on ships, and a prolonged land sickness, when they get off the ship. This rare disorder is called "mal de debarquement", which is French for "bad getting off the ship". Persons with unusually good vestibular function may be more susceptible to motion sickness than others (Gordon et al, 1996).

Migraine is a definite risk factor for motion sickness, with roughly a 5 fold greater incidence than non-migraineurs. Female gender and youth is also a risk factor. In women, days 9-15 of the menstrual cycle appear to have a higher incidence of nausea (Ramsay, 1994) but not all agree Cheung, B., R. Heskin, et al. (2001). Medications that prevent migraine may also prevent motion sickness (see below).

Experimentally, motion-sickness can be eliminated in dogs by surgically removing part of the brain (the nodulus, according to Bard). Motion sickness is sometimes associated with prolonged vestibular responses (Hoffer et al. 2003).

Motion sickness immunity is generally found in persons with absent vestibular responses (William James; Cheung et al. 1991). Age is probably not a large factor in motion sickness (Cheung andMoney, 1992)although children below the age of 2 are said to be immune.

Treatment of Motion sickness:

There are four strategies to treat motion sickness:

• Behavioral (avoidance, mental activities)
• Medication (conventional, alternative)
• Stimulation (alternative)
• Exercise (habituation)

Behavioral Strategies for Motion Sickness

• In the car: sit in the front seat or drive.
• Aboard a ship: stay toward the middle and look at the horizon. Avoid ship travel if possible. Stay out of small tight places where you can't see the horizon.
• On the airplane: ask for a window seat. The front of the plane may be preferable, as it is usually less noisy. Some people find that sitting in the middle is the best location as it provides one with a better appreciation of the aircraft's tilt. Don't sit near the bulkhead as this gives you no visual help to figure out how much you are really tilted.
• For cars: It may be helpful to mentally rehearse a trip route as familiarity and anticipation is sometimes helpful.
• Face leeward (so if you vomit, it gets blown away from the ship, not into it).
• Eat bland foods -- crackers and bread, or bananas, rice, applesauce and toast.

Most medications for motion sickness need to be taken at least 30 minutes before exposure to the activity that can cause the problem. Persons with glaucoma or prostate problems should not take most of these medications unless so advised by their doctor.

• Antihistamines
  • Meclizine (Antivert, Bonine). In the antihistamine family. Can cause drowsiness. Like other most other medications, it is best to take these before motion stimulation.
  • Dimenhydrinate (Dramamine). Similar to meclizine. Liquid forms are available for children 2 years of age or more.
  • Cyclizine is similar to meclizine. It is suitable for children 6 years of age or older as well as adults. It is most useful in situations involving short trips (e.g. automobile).
• Haldol, Thorazine -- these anti-psychotic drugs have dopamine blocking activity which is useful for blocking nausea as well as stimulating stomach motion which helps clear food from the digestive tract.
• Promethazine. This drug is one of the most effective available for motion sickness. One dose lasts up to 8 hours. Like the other drugs, it can cause drowsiness.
• Diazepam (valium) and related "benzodiazepine" medications such as lorazepam and klonazepam. While these drugs are not traditionally used for motion sickness, some people find them useful in small amounts. These medications are very helpful for a related condition, MDD.
• Scopolamine patches -- these patches are sometimes very helpful. They are a time release form of an anticholinergic medication, scopolamine. Scopolamine is also available in pill format (usually given for irritable bowel). Scopolamine was found the most useful medication for prevention of motion sickness induced by cross-coriolis stimulation (Dornhoffer et al, 2004). Whether or not this is true for other types of motion stimulation is not known.
• Zofran and other serotonin-family anti nausea drugs -- these are powerful anti-nausea medications. They do not prevent motion sickness but they may prevent vomiting.
• Other medications.
  • Migraine medications: Verapamil (a calcium channel blocker), venlafaxine (an antidepressant)
  • Seizure medications phenytoin and carbamazepine (sodium channel blockers)
  • Non-benzodiazepine anxiety medications. Buspirone (Buspar)
  • Alternative medications Beta-histine (Serc). This medication is sometimes very effective. (e.g. Matsnev and Sigaleva, 2007).
• Medications that don't work for motion sickness:
  • antihistamines such as fexofenadine and cetirizine that do not get into the brain (Cheung, B. S., R. Heskin, et al.; 2003).

Medications for nausea and vomiting

Treatment of motion sickness differs from treatment of nausea and vomiting. A discussion of the treatment of vomiting can be found here.

Stimulators for Motion Sickness

There are several devices that are advertised to reduce motion sickness through stimulation of various places on the body (usually the wrist). These include "Sea Bands" and "Relief Band", among others. These devices are probably placebos. Nevertheless we have encountered some people who have had success.

Exercises for motion sickness.

It is reasonable to assume that habituation (repeated motion exposure) makes one less motion sensitive. (Cheung, B. and K. Hofer, 2005). In fact, the military uses a "habituation" protocol to overcome motion sickness. This requires expensive equipment (a rotating chair).

The recently has been an home exercise method proposed to overcome motion sickness -- the "Puma" method. These exercises were developed by a flight surgeon (Dr. Puma), to assist pilots with motion sickness in overcoming their sensitivity. They are very stimulating exercises, that may be useful to extremely motivated people, who are not able to use more conventional methods of management of motion sickness such as medications

The Puma method appears to us to be a habituation protocol -- repeated exposure to the things that make one ill. This may well work -- if you can tolerate the process. We are cautiously hopeful about this method -- although it seems to us to be likely to cause a lot of nausea itself. If you are interested in trying the Puma exercises, you can order a copy through this link.

Our thought is that activities that promote formation of "internal models" of motion may also be useful for motion sickness prevention. We do not know of any formal protocols that use this idea.

We recently have proposed a protocol for visual dependence that may be useful in treatment of motion sickness (Chang and Hain, 2007). See the page on visual dependence for more detail.

Alternative medications

There are numerous "alternative" remedies for motion sickness. The most popular are Ginger derivatives, such as ginger tea, powdered ginger capsules, and even raw ginger between the teeth. We have not seen much success in our patients.

See also: http://www.sciam.com/askexpert_question.cfm?chanID=sa005&articleID=00007F4B-D6FD-1E4B-967D809EC588EEDF

REFERENCES:

• Benson AJ. Motion Sickness. In Encyclopaedia of occupational health and safety,
• Chang CP, Hain TC. "A theory for treating visual vertigo due to optical flow" CyberPsychology and Behavior. 9-2007
• Cheung, B., R. Heskin, et al. (2001). "The menstrual cycle and susceptibility to coriolis-induced sickness." J Vestib Res 11(2): 129-36.
• Cheung, B. and K. Hofer (2002). "Lack of gender difference in motion sickness induced by vestibular Coriolis cross-coupling." J Vestib Res 12(4): 191-200.
• Cheung, B. and K. Hofer (2005). "Desensitization to strong vestibular stimuli improves tolerance to simulated aircraft motion." Aviat Space Environ Med 76(12): 1099-104.
• Cheung, B. S., R. Heskin, et al. (2003). "Failure of cetirizine and fexofenadine to prevent motion sickness." Ann Pharmacother 37(2): 173-7.
• Cheung, B. S., I. P. Howard, et al. (1991). "Visually-induced sickness in normal and bilaterally labyrinthine-defective subjects." Aviat Space Environ Med 62(6): 527-31.
• Cheung, B. S., R. L. Kohl, et al. (1994). "Etiologic significance of arginine vasopressin in motion sickness." J Clin Pharmacol 34(6): 664-70.
• Cheung, B. S. and K. E. Money (1992). "The influence of age on susceptibility to motion sickness in monkeys." J Vestib Res 2(3): 247-55.
• Cheung, B. S., K. E. Money, et al. (1992). "Investigation of anti-motion sickness drugs in the squirrel monkey." J Clin Pharmacol 32(2): 163-75.
• Dornhoffer J, Chelonis JJ, Blake D. Stimulation of the semicircular canals via the rotary chair as a means to test pharmacologic countermeasures for space motion sickness. Otol Neurol 25: 740-745, 2004
• Gordon CR, Spitzer O, Doweck I, Shupak A, Gadoth N. The vestibulo-ocular reflex and seasickness susceptibility. J Vestibular Res. 6, 229-233, 1996
• Hain TC, Oman CM. Why does reading in a moving car cause motion sickness ? Scientific American, July 2003, p. 93
• Hoffer ME, Gottshall K, Kopke RD, Weisskopf P, Moore R, Allen KA and Wester D (2003). "Vestibular testing abnormalities in individuals with motion sickness." Otol Neurotol 24(4): 633-6.
• Lawthor A, Griffin MJ. A survey of the occurence of motion sickness amongst passengers at sea. Aviat, Space and Env Med 1988, 59, 5, 399-406
• Ramsay TM, McDonald PF, Faragher EB. The menstrual cycle and nausea or vomiting after wisdom teeth extraction. Can J. Anaesth 1994, 798-801.
• Sharma K, Aparna. Prevalence and correlates of susceptibility to motion sickness. Acta genet med gemellol (roma) 1997;46(2); 105-21
• Turner M, Griffin MJ. Motion sickness incidence during a round-the-world yacht race. Aviat Space Environ Med 1995, 66, 849-56
• Wright MS, Bose CL, Stiles AD. The incidence and effects of motion sickness among medical attendants during transport. J. Emerg Med 1995, 13, 15-20

Acknowledgements:

• We thank several readers who have offered their observations regarding motion sickness strategies.