What are the treatment options for motion sickness?

Treatment of Motion Sickness

For motion sickness prevention, scopolamine transdermal patch applied at least 4 hours before exposure is the first-line treatment, with meclizine 12.5-25 mg three times daily as the preferred alternative when scopolamine cannot be used. 1, 2

First-Line Pharmacological Treatment

Scopolamine Transdermal System

• Scopolamine is the most effective first-line medication for motion sickness prevention, working as an anticholinergic agent by blocking acetylcholine to reduce neural mismatch. 1, 3
• The transdermal patch should be applied to a hairless area behind one ear at least 4 hours (ideally 6-8 hours) before anticipated motion exposure. 1, 2
• Each patch delivers approximately 1 mg over 3 days; if treatment is needed longer than 3 days, remove the patch and apply a new one behind the opposite ear. 2
• FDA clinical trials demonstrated a 75% reduction in motion-induced nausea and vomiting when applied 4-16 hours prior to motion exposure. 2
• Critical administration detail: Wash hands immediately after application to prevent accidental eye contact, which can cause pupil dilation and blurred vision. 2

Antihistamines (Second-Line)

• Meclizine 12.5-25 mg three times daily is recommended for patients who cannot use scopolamine due to contraindications or side effects. 1
• Antihistamines suppress the central emetic center, with first-generation agents preventing symptoms in approximately 40% of susceptible individuals compared to 25% with placebo. 1, 4
• Dimenhydrinate (100 mg) is somewhat more effective against nausea than single-dose scopolamine but must be taken before departure. 5, 6

Severe or Refractory Cases

Combination and Alternative Therapy

• For severe symptoms requiring rapid onset, promethazine 12.5-25 mg can be used, though it carries more side effects including sedation, hypotension, and extrapyramidal symptoms. 1
• Scopolamine transdermal patch and meclizine can be used together when severe symptoms require combination therapy, providing complementary mechanisms of action. 1
• Ondansetron 8 mg every 4-6 hours (sublingual formulation preferred) may be considered, though a baseline ECG is recommended due to QTc prolongation risk. 1
• Prochlorperazine may be used for short-term management of severe nausea or vomiting in severely symptomatic patients. 7

Special Populations

Children

• Children under 6 years should NOT use over-the-counter antihistamines for motion sickness due to potential toxicity—between 1969-2006, there were 69 fatalities associated with antihistamines in children under 6 years. 4
• For children who can take antihistamines, watch for paradoxical behavioral disinhibition, especially in younger children. 4
• Sedation occurs in approximately 66% of patients on antihistamines; close monitoring is necessary for anticholinergic side effects including blurred vision and cognitive impairment. 4

Elderly Patients

• Elderly patients are at higher risk for anticholinergic side effects and should be monitored closely when using scopolamine and meclizine. 1
• Anticholinergic medications are an independent risk factor for falls in elderly patients. 1

Critical Pitfalls to Avoid

Duration of Use

• Vestibular suppressant medications should NOT be used for long-term treatment as they interfere with central compensation in peripheral vestibular conditions and prevent natural adaptation to motion. 1, 7, 4
• Long-term use of antihistamines or benzodiazepines interferes with natural vestibular compensation and adaptation. 1

Withdrawal Symptoms

• Withdrawal symptoms can occur 24 hours or more after removing scopolamine patch after several days of use, including difficulty with balance, dizziness, nausea, vomiting, confusion, muscle weakness, low heart rate, or low blood pressure. 2
• If withdrawal symptoms become severe, patients should contact their physician immediately. 2

Medications to Avoid

• Benzodiazepines should be avoided for motion sickness due to lack of efficacy and significant harm potential. 1
• Nonsedating antihistamines, ondansetron (as primary prevention), and ginger root are NOT effective for motion sickness prevention. 3

Adjunctive Measures

• Prokinetic antiemetics such as metoclopramide can be useful adjuncts for managing nausea and vomiting associated with motion sickness. 7
• Non-pharmacological approaches (distraction techniques, audio-visual entertainment, relaxation methods) should be considered first for children who cannot take antihistamines. 4