The chemical nepetalactone is to credit for your kitty's crazy reaction to catnip. The chemical, which is a mild hallucinogen, doesn't affect humans in the same sense as we do not rely as heavily on our noses as cats do. In fact, it doesn't even affect all cats.
Finasteride is a drug that belongs to the class of androgen inhibitors, which means that it blocks the production of male sex hormones. It is sold in the United States and Canada under the brand names Proscar and Propecia.
Finasteride (Propecia) is approved by the Food and Drug Administration to treat male pattern hair loss (also called androgenetic alopecia). At higher doses, it's also approved to reduce the symptoms of enlarged prostate in men.