Q&A: Can I give my child Benadryl on long plane or car rides?

No! We understand the temptation, and you're not the only parent asking. (Just look around a crowded plane the next time you're boarding, and you may see lots of parents pulling out packs of over-the-counter medicines.) Because while you may take Benadryl (dipenhydramine) for quick (and sleepy) relief for hay fever symptoms, it's just not OK to casually give these or nighttime cough and cold medications to young children. Why?

It could be dangerous. In June 2008 the American Academy of Pediatrics (AAP) released a statement saying that over-the-counter cough and cold medications should not be given to infants and children younger than 2 years of age, due to the risk of life-threatening side effects. They report: "Studies show that cold and cough products don't work in children younger than 6 years and can have potentially serious side effects." And antihistamines are only to be used for young children with known allergies. (See our Benadryl dosage chart here and consult with your pediatrician before offering it to your child for the first time.)

It might not work—and could backfire. A study done at Johns Hopkins and reported in the Archives of Pediatrics and Adolescent Medicine in July 2006 showed that giving dipenhydramine to help with infant rest did not help children sleep—and in some cases it had the opposite effect. Many children can experience hyperactivity when taking this medication. (This side effect of hyperactivity can be present in older children and adults as well.)

The bottom line is this: Only use Benadryl or other over-the-counter medications under the guidance of your doctor. If she does advise use of meds, be very clear on the recommended dosage—even if a medicine is available without prescription, it should be treated with care and used only as directed.

If you're looking for your child to sleep on the ride, let her run around and play hard before you board or get on the road, and then bring some novel toys to keep her occupied on the way. (Check out this travel guide for more ideas.) Good luck!