Symptoms of motion sickness can range from mild to severe. Mild symptoms include uneasiness, headache, and nausea. Severe symptoms include vomiting, dizziness, fatigue, weakness, inability to concentrate, excessive sweating and salivation, and severe distress. Prolonged motion sickness can produce depression, low blood pressure, dehydration, or worsen the condition of people who are already ill due to other factors.
Motion sickness is caused by the effects of movement on the inner ear, which helps control balance. Other contributing factors include anxiety, movement immediately after eating or eating too much, and poor ventilation.
Note: For people who are prone to motion sickness, having a bowel elimination before traveling can minimize the likelihood of an attack.