The cat herbs.
Valerian and catnip both have a reputation of driving cats wild.
So the usual herbal cat toys contain either catnip (Nepeta cataria) or valerian (Valeriana spp.). Or one or the other milder aromatic mint (I've heard of Agastaches and Monardas being used, and I'm sure there's others) but they're used much more rarely.
The usual is, fill a sock with fresh catnip flowers or dried valerian root, tie it to a rubber band, tie that to a doorknob and watch your cat have fun.
But: I'm told that the reason for some (not all) cats going wild over one or both of these plants is pheromones.
The poor things think they're getting some.
And I've completely and utterly forgotten where I've picked this tidbit up, sorry. I can't even say in what language I've read (or heard) it, let alone who told me.
Anyway, the drooling, the mindlessness, the headrubbing all over the herb, the "can't walk straight" thing - that's all signs of a cat in heat.
Now, be honest: do you want to give your cat(s) that disappointment?
There's this saying that female cats like catnip while male cats like valerian.
A couple years ago one neighbor had a male and female cat, and I called them with fresh catnip flowers in one hand and dried valerian root in the other. Both went to the valerian. A year or two later, a new neighbor moves in, with another male and a female cat. I try again, and this time both cats go for the catnip - and sniff around. I knew I shouldn't have done that test so close to my garden -- that catnip plant was tall and proud before, but a day later only one branch was left, and that only because it was almost groundbound.
Anyway, I'm not giving either herb to cats, anymore. I believe in truth in advertising - and these don't advertise truthfully.