However, using Atarax (hydroxyzine) to help a one-year-old sleep during a flight is not recommended. Antihistamines can sometimes cause a paradoxical reaction in young children, making them hyperactive rather than sleepy, and can pose breathing risks. Because safety is our top priority, we cannot recommend a dosage for travel sedation. I gently encourage you to speak with your pediatrician before giving any medication. For the flight, natural soothing methods like feeding during takeoff and landing, favorite toys, and extra cuddles are much safer ways to comfort your baby.