Long ago I used that antihistamine when visiting people who had cats that I'm very allergic to. I used it simply because it was the absolute cheapest allergy pill around at $2.75 for a bottle of 100 pills.
Nothing special about it that I ever noticed. It's just an allergy pill.
Didn't really sedate me, but then I've yet to find any antihistamine to be noticeably sedating and I used allergy pills way back in ye olden days before the newer generation of "non-sedating" ones came to market.
it has a peculiar side-effect profile compared to other antihistamines, since *excitation*, not sedation is reported at higher doses, especially in children..
I wouldn't make much of that, since paradoxical effects are most commonly seen in the very young and very old. Things like Benadryl that will sedate most making some kids hyper, or Valium being able to agitate someone who's 85 even though it's a chill pill to most.
I never noticed it to produce excitation either. Seemed like any other allergy pill to me, with price being the only factor favoring it. Keep in mind that when I used it a decade+ ago I was subject to no potential placebo effect, since I didn't expect it to do anything other than keep me from having an allergic reaction to cats (that are very cute, but secretly have an evil plot of make my eyes swell shut). I had to take in in amounts higher than recommended just to survive exposure to cats.
As for the comment about not mixing it with MAOIs, I've never heard of any antihistamine that was a problem with MAOIs before. Can anyone else confirm this? Typically MAOI problems come up when you have multi-ingredient meds for colds & allergies and one of those ingredients is typically psudoephedrine (Sudafed) that's tossed in to deal with nasal congestion that so often comes with allergies & colds.
As for long-term harm, there are people who take allergy meds daily forever, so if there was a risk one would think it would be readily apparent after over half a century of use.