Quote:
Originally Posted by mrsD
I always thought that Dramamine was first generation, and Benadryl. Chlorpheniramine and Dex, and bromo were 2nd, and
the new ones like Claritin, Allegra 3rd. Back when the pheniramines were advertised and promoted, they were suggested as "less drowsy" than Benadryl and Atarax tended to be.
But some places list them differently.
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I've always seen the pheniramines listed as first-generation, the distinction being that they do cross the BBB significantly and also have some, albeit less, anticholinergic activity.
The delineation between second and third is imho hazier. Most of the "third-generation ones are refinements of second-generation ones but do not exhibit significant differences (eg. 2nd-cetirizine/3rd-levocetirizine) other than with terfenadine/fexofenadine, in which case the first had toxic interactions while its metabolite does not. Now, I *have* seen the so-called third generation ones sometimes lumped together with second generation, which makes sense to me because their behavior is not significantly different.
Not terrribly surprised though that you have seen the classifications listed differently for the pheniramines. It sounds like they might have been proposed as a newer generation when they first came out. Interesting.
These "delineations" and what falls under each umbreall probably changes somewhat over time.
For Steve's purposes, I stand by my previous recommendations to him, including the notes to retry chlorpheniramine since dexchlorpheniramine was getting the job done for him.
waves