Abstract: The invention provides a method for improving hair biology, e.g., hair growth. The method comprises administering to a subject a monoamine oxidase inhibitor and a vasodilator, a zinc salt of a carboxylic acid, a xanthine compound, pyrithione or a salt thereof, saponin, tritapene, crataegolic acid, celastrol, asiatic acid, an inhibitor of 5-alpha-reductase, 1,4-methyl-4-azasteroid, an androgen receptor antagonist, azelaic acid or a derivate thereof, cyclosporin, triiodothyronine, diazoxide, retinoic acid, a prostaglandin analog, aminexil, carnitine tartrate, apigenin, procapil, or adenosine, in an amount effective to achieve a desired effect. The invention further provides a method of reducing or delaying the appearance of an age-related skin imperfection. The method comprises administering to the subject a composition comprising an MAO inhibitor. A kit for improving hair growth also is provided.

Abstract: The invention provides a method for improving hair biology, e.g., hair growth. The method comprises administering to a subject a monoamine oxidase inhibitor and a vasodilator, a zinc salt of a carboxylic acid, a xanthine compound, pyrithione or a salt thereof, saponin, tritapene, crataegolic acid, celastrol, asiatic acid, an inhibitor of 5-alpha-reductase, 1,4-methyl-4-azasteroid, an androgen receptor antagonist, azelaic acid or a derivate thereof, cyclosporin, triiodothyronine, diazoxide, retinoic acid, a prostaglandin analogue, aminexil, carnitine tartrate, apigenin, procapil, or adenosine, in an amount effective to achieve a desired effect. The invention further provides a method of reducing or delaying the appearance of an age-related skin imperfection. The method comprises administering to the subject a composition comprising an MAO inhibitor. A kit for improving hair growth also is provided.

Abstract: Disclosed in a hair care composition comprising: (i) a hair diameter increasing agent comprising a xanthine compound, a vitamin B3 compound, and a panthenol compound; and (ii) an carrier comprising water and monohydric alcohols having 1 to 6 carbons; wherein the monohydric alcohol is present in the composition at a level by weight of from about 10% to about 90%, preferably from about 30% to 90%, and wherein the composition may further comprises a substantially soluble silicone conditioning agent and/or a thickener. The hair care compositions of the present invention provide improved hair diameter increase benefit. The hair care compositions of the present invention also provide improved feel during usage and/or after usage, while not-compromising the penetration of the hair diameter increasing agent.