Some cats are more susceptible to catnip. I had one that it didn’t do anything for her. I grew some catmint in my garden and that was a different story!!

According to a recent paper, catnip works through the body’s internal opioid system. When a cat smells catnip, a substance called nepetalactone interacts with certain cells in their upper airway. Once the interaction occurs, the cat’s body releases endorphins—natural opioids.

This theory is supported by the fact that cats who receive the opioid “antidote” naloxone are not affected by catnip. Ingestion alone seems to have little effect on cats, although some may chew on the herb, perhaps to release the nepetalactone, especially from drier leaves.

Although reports that the herb induces LSD-like hallucinations are probably overblown (and difficult to prove), catnip is nonetheless a safe, cheap, and effective way to give your cat some short-lived enjoyment.

[petmd.com]