Topic: The big central furdope list....
...err.... as pertains to the fur itself, at least.
Releases substance p, which... makes hair grow.
Yeah. Pepper-spray whole self, become kitteh. Applied topically.
Standard KATP channel openers of the sulfonylurea receptor, of which minoxidil is most famous, and is actually sold OTC as furdope.
...sadly, I will probably not be nominated for a nobel prize for the "potassium furdope hypotheosis" due to previous work. Despite this, "we still have no idea how it works" gets written in the literature... a lot, for some reason.
Applied topically or systemically - usually topically. Side effects of extreme overdose include dangerously low blood pressure.
Or as most people call it, cortisol. Maybe it's the Na+/K+ balance, maybe it's the alteration of the glucocorticoid/defurring-mineralcorticoid balance, maybe it's induced cushings, maybe it's just skin damage from corticoids in general...
...it's a listed side effect. Applied topically.
IL-1/2 inhibitors (cyclosporin a, etc)
Literally the leading side effect. Historically, ingested systemically. Topical would be interesting, though penetration would be hard.
Main effect is immunosuppression, so topical woo-peptides are closest to safe. That's right, the reason you're not furry is... lupus, lol. Other antagonist (anakira, tacrolimus, picrolimus) are also generally fur-inducing.
Usually things such as apomorphine and bromocriptine. Tend to be direct nauseants, conversely, do not take ginger or other antinauseant drugs. Should be dosed at a sub-vomit level.
Used orally. Shuts down prolactin, and prolactin shuts down hair growth.
Prolactin also suppresses androgen and estrogen production.
The hypertrichosis you get from the cast rubbing on you can be yours with a dermaroller.
The MTM/FTM minoxidil beard community seems to think that T will cheerfully convert enhanced vellous growth to terminal growth, setting your gainz. On the one hand, this can get you off the dope. On the other hand, it means "fur switch" is pretty non-guaranteed past about five years of age. Worse still, reports are... widely mixed... and there's even less "minoxidil forehead" data.
Briefly taking on a little extra T, say high-male, can probably help that, especially topically applied. Minoxidil itself, ironically...
...is an antiandrogen.
So, there it is. Most of the dope is OTC - just mix Rogaine/hydrocortizone/jalapeno extract, and you've got a topical furdope ointment - with prolactin/il1/2 inhibitors for the fancy folks, and maybe add a topical irritation such as dermarolling or other microneedling... and you've got fur at least temporarily and moderately likely permanently. Likely finish off with topical testosterone as needed - high point levels with reduced systemic.
Please note that minoxidil is informally reputed as being profoundly toxic to cats in even the smallest doses. Also note that this will turn you into a furry... human. Brows pics of hypertrichosis/werewolf syndrome/etc to see if you like this form, other work not included. Still, you can probably do a bit with just hairstyling.
All-OTC ointment with supps and technique, hairstyling and extra work not included.
Good luck - and have fun slinging the package.