signaling protein that, when suppressed, may grow hair by reducing inflammation and stem cell loss  
        glycoprotein that inhibits TGF-β and promotes hair growth by antagonizing activin  
        An essential vasodilator with some anti-androgenic effects, has excellent safety record  
        highly targeted anti-androgen that might have minimal systemic effects  
        a potent but unapproved and potentially problematic topical anti-androgen