Does anyone else have experience using antihistamines as a nootropic?

I actually learned about this on TikTok. Apparently, it’s surprisingly effective for managing PMS symptoms, which led to some further digging.

I’m male, Costco impulse buy — I picked up some Pepcid AC (Famotidine 20mg, an antihistamine). I’ve noticed a marked improvement in anxiety whenever I take one.

Histamines, which I originally only associated with allergies, can cause other problems and are linked to lots of other health issues like anxiety, insomnia, brain fog, and irritability.

So it would follow that an antihistamine could be beneficial (simple logic like this isn’t always true, though!).

Whenever I take one, I feel calmer, more clear-headed, and more present. But I know that taking it for more than two weeks isn’t recommended.

I was wondering if anyone knows of a different antihistamine that could have the same effect but is safe for long-term use? Or if taking half a pill daily or one every other day might work better?

Can’t discount that this could all be placebo — but hey, I’ll play the game.

Thank you in advance ✌🏻