Going along with
all4fun here. Dr Sears is a very trusted doctor (and father of several).
I just had an experience with a prescription drug like benadryl, where the dentist required DS to have it before his appointment, I stupidly went along with it, and DS was bouncing off the walls for the rest of the day. It did NOT calm him down, and DS was an angry, furious, tasmanian devil who refused a nap, despite getting up VERY early for the appointment, until 5pm in the afternoon (he's 3 but he still likes his 2 hour nap normally at 1 or 2).
That said, I think drugging a kiddo for the *possible* convenience for a flight is a tricky one. If they react opposite (and just b/c they respond sleepily to it once doesn't mean they will every time...I myself have random reactions to OTCs depending on the day), it's going to be a rotten experience.
Plus, and this is IMO, you're taking away the truly FUN experience of flying...maybe they wont' like it, but maybe they'll be like my boy and really enjoy the vast experiences of flying...seeing the often-pretty (or maybe i'm just spoiled with SeaTac's updates) airports, seeing all those people, interacting with kind flight attendants, and so on and so forth. My guy hasn't been an angel, but he's enjoyed quite a bit of the flights he's been on.
Anyway, your ped has recommended this, but many others do NOT.
Oh and homeopathic remedies are AMAZING. We've had great luck with Rescue Remedy (to calm EVERYONE down). Boiron brand chamomile used to work great until DS got ahold of the whole bottle and it hasn't worked since.
