The studies behind our verdicts

Annals of Emergency Medicine 68(1):1-9.e1 · PMID 26679977

Inhaled isopropyl alcohol produced markedly greater nausea relief than inhaled saline placebo at 30 minutes: around a 30 mm reduction on a visual analogue scale, against 9 mm for ondansetron. No adverse events reported. The population was emergency-department nausea, not motion sickness.

Aviation, Space, and Environmental Medicine 78(4):408-13 · PMID 17484344

Of four airsickness countermeasures tested in a recreated helicopter troop transport, only promethazine 25 mg plus caffeine 200 mg significantly reduced nausea and sickness severity compared with its placebo. Caffeine was never given alone in this study, so its share of the effect is unknown.

Journal of NeuroEngineering and Rehabilitation · PMC12882250

Hion-brand fluid-filled motion sickness glasses versus identical drained-fluid placebo glasses during a simulated “scrambler” ride: no significant difference in symptom rise between groups (median MSAQ increase 31.0 vs 16.0, p = 0.15). The authors note the study was underpowered for small effects and participants were not told to fixate a stationary object as the manufacturer recommends.

Acta Oto-Laryngologica 105(1-2):45-9 · PMID 3277342

Cadets given 1 g of powdered ginger root reported less vomiting and fewer cold sweats than the placebo group, with the difference reaching statistical significance (p < 0.05) four hours after dosing.

Acta Oto-Laryngologica 105(1-2):45-9 · PMID 3277342

Cadets given 1 g of powdered ginger root reported less vomiting and fewer cold sweats than the placebo group. This tested a measured dose of the root, not ginger ale.

Cochrane Database of Systematic Reviews, CD007598 (2018 update)

Aromatherapy was not found to be effective in reducing nausea severity compared with placebo, with the quality of evidence rated low. This is post-operative nausea, not motion sickness.

Gastroenterology 102(6):1854-8 · PMID 1587405

Electrical acustimulation reduced symptom scores and irregular gastric activity versus no stimulation, and the acustimulation group had lower symptom severity than both sham-stimulation and control groups. Authors concluded it reduces motion sickness symptom severity and appears to decrease gastric tachyarrhythmia.

Aviation, Space, and Environmental Medicine 66(7):631-4 · PMID 7575310

P6 acupressure produced significantly less nausea during drum rotation than sham acupressure, dummy-point acupressure and control (p < 0.0001), along with less abnormal gastric activity. Dummy-point acupressure did not produce the benefit.

Experimental Brain Research 240(2):651-663 · PMID 34997261

Peppermint gum did not outperform ginger gum in visually induced motion sickness; pleasant taste rather than the specific botanical was associated with less sickness.

Experimental Brain Research 240(2):651-663 · PMID 34997261

Induced measurable motion sickness using a visual stimulus alone, confirming that what your eyes are given is sufficient to cause symptoms without any unusual vehicle motion.

Experimental Brain Research 240(2):651-663 · PMID 34997261

Peak Fast Motion Sickness Scale scores were reduced by 2.05 points (SE 0.76) in the chewing gum groups versus control, d = 0.65, p < 0.01, after a 15-minute VR helicopter flight. Ginger gum was not superior to peppermint gum. Pleasant taste was associated with less sickness.

Applied Ergonomics 45(3):521-7 · PMID 23957932

Watching a 14-minute bicycle-ride video with relaxing, neutral, stressful or no music: a significant reduction in visually induced motion sickness occurred only when the presented music was rated pleasant by the listener, independent of the assigned music category.

Experimental Brain Research 233(5):1353-64 · PMID 25633319

Only about half of those exposed to a scent noticed it. Among those who noticed a rose scent, visually induced motion sickness was less severe than in people who did not notice a scent. This tested rose, not lemon.

Am J Physiol Gastrointest Liver Physiol 284(3):G481-9 · PMID 12576305

Ginger pretreatment (1,000 and 2,000 mg) reduced the nausea of circular vection, delayed its onset, shortened recovery, and reduced tachygastria and plasma vasopressin: evidence the effect is gastric rather than vestibular.

Am J Physiol Gastrointest Liver Physiol 284(3):G481-9 · PMID 12576305

Showed that motion sickness involves measurable disruption of gastric rhythm, and that an intervention acting on the stomach reduced nausea, indirect support for the stomach's state mattering, though it tested ginger rather than food.

Aviation, Space, and Environmental Medicine 75(3):227-34 · PMID 15018290

Acuband and ReliefBand, worn by trained and untrained subjects, versus placebo, under optokinetic drum rotation. Authors' conclusion: neither band nor placebo prevented the development of motion sickness, regardless of whether the bands were used correctly or incorrectly.

Aviation, Space, and Environmental Medicine 75(3):227-34 · PMID 15018290

Tested a ReliefBand alongside an acupressure band under optokinetic drum rotation. Neither band prevented the development of motion sickness, whether worn correctly or incorrectly.

Neuroscience Letters 566:326-30 · PMID 24602977

Smelling limonene, a pleasant citrus odor, or petrol during off-vertical-axis rotation did not change motion sickness symptoms compared with distilled water.

Ergonomics 34(7):867-79

Deliberately equated its groups for vision as well as head movement and predictability, which is what lets the coach-travel finding be read as a visual effect rather than a by-product of where people sat.

Ergonomics 34(7):867-79

Subjects with control over nauseogenic rotation reported significantly fewer motion sickness symptoms and less decrement in well-being than their yoked partners receiving the identical motion stimulus, with groups equated for head movement, vision, activity and predictability.

Journal of Travel Medicine 1(4):203-206 · PMID 9815340

Seven seasickness medicines were compared, including dimenhydrinate with caffeine and meclozine with caffeine. There was no placebo group. Vomiting ranged from 4.1% to 10.2% across groups with no significant difference, so the study says nothing about caffeine on its own.

Applied Ergonomics 90:103264 · PMID 32920224

14 days of 15-minute pen-and-paper visuospatial training raised visuospatial scores about 40%, and was followed by 51% less motion sickness in a simulator and 58% less on the road.

Ergonomics 42(3):444-61 · PMID 10048305

Illness was reported by a mean 34.6% of passengers with no view of the road ahead, against 12.7% of those who could see it extremely well, about a threefold difference. The authors concluded travel sickness could be significantly reduced by improving passengers' external visibility.

Ergonomics 42(3):444-61 · PMID 10048305

Found forward visibility strongly predicted sickness in real passengers, the part of the driver's advantage that a passenger can most easily copy.

Ergonomics 42(3):444-61 · PMID 10048305

Establishes that visual input strongly influences sickness: passengers without a forward view fared far worse. It supports the mechanism eye-closure relies on without testing eye closure itself.

Ergonomics 42(3):444-61 · PMID 10048305

Illness was reported by 34.6% of passengers with no view of the road ahead against 12.7% of those who could see it extremely well, about a threefold difference from visual input alone. A phone is the strongest available version of 'no forward view'.

Collabra: Psychology 10(1):121390

Same 14-day, 15-minute-per-day visuospatial training against a no-training control, either side of a 30-minute simulated drive. Sickness fell from the first drive to the second, but the training had no significant effect on that fall; Bayesian analyses gave clear evidence in favour of the null.

Journal of Clinical Pharmacology 32(11):1008-12 · PMID 1474161

Injected 30 minutes before rotation, promethazine 25 mg and scopolamine 0.2 mg significantly increased the number of head movements people tolerated compared with placebo. Caffeine 250 mg did not have a significant effect.

Journal of Travel Medicine 10(2):108-11 · PMID 12650654

Motion tolerance before moderate nausea: controlled breathing 10.7 ± 5.6 min versus control 9.2 ± 5.9 min (p < 0.01). Authors described the effect as about half as effective as standard doses of oral scopolamine, but free of side effects.

Journal of Travel Medicine 10(2):108-11 · PMID 12650654

A music audiotape extended motion tolerance before moderate nausea to 10.4 ± 5.6 min versus 9.2 ± 5.9 min for the control condition (p < 0.01), a benefit similar in size to controlled breathing in the same trial.

Explore (NY) 22(5):103470 · PMID 42330915

With a lemon essential oil aromatherapy mask on the second ride, the median Graybiel symptom score fell from 18 to 6 (P < 0.001), with lower nausea, pallor, cold sweating and salivation. The lemon ride always came second.