I want to put in my 2 cents here. I have always given my children benadryl on plane rides. Yes, benadryl is an allergy med and is used as a sleep aid and is in medication like Tylenol PM. But, it is also used for motion sickness.
So lets see for a child that has pressure in ears or sinus area related to flying benadryl will help or has motion sickness it will help. My children have flown numerous times since 9 months old and have never had ear pain, nausea or any other problems with flying, never any crying or screaming because thier ears hurt. Yes, the added benifit of lethargia/sleepiness is a plus, that is not the only reason it is a benifit. It also makes the flight more physically comfortable for the child. You, wouldn't deny your child or your self any pain meds. after an injury or tylenol for a headache, why not make thier flight more comfortable.
So, don't think of it just as a sleep aid. Think it as a prophylactic to make you child comfortable during a flight. The only time you might not want to give your child benadryl is if they are ADHD because it might have the complete oppisite affect on them.[/QUO
Okay - to address a few of these comments, Benadryl does nothing for travel or sickness related ear pain, sinus pain, nausea, etc. It is an allergy medication and one I know well as I suffer from seasonal allergies. If the stuffiness, etc. is an allergic reaction, yes Benadryl may help. If on the otherhand it's related to pressure changes or having a cold, it does NOTHING. Also, while I do give my children and myself medication if we are suffering, I can't imagine medicating them in case they got sick
As for your comment about it being a "prophalactic to make your child comfortable during a flight" - how about waiting to see how your child handles a flight before assuming they need medication? You might be pleasantly suprised.
Also, if anyone is looking for ways to avoid / relieve ear pain while flying here a few pediatrician reccomended ones that have always worked for us:
for a nursing infant/toddler: nurse them during takeoff and landing
if your baby uses a bottle, offer it to them during the same times.
for toddler / preschoolers; they sell lollipops with loop handles which are safer or a small juice box / sippy cup and having them take frequent small sips.
older children: chewing gum, lollipops, hard candies, starburst, etc.
To the Op andanyone traveling with a small child: the best advice is plan well for their every need and they will likely suprise you by being a great traveling companion. They are fasicnated by airports, planes, watching people, etc and the trip there is a learning experience in how to behave that is invaluable. Don't assume they aren't up to the challenge.