TRANSDERMAL HORMONE SPRAY

1 . A transdermal estrogen spray composition, comprising:

a therapeutically effective amount of an estrogen;

a penetration enhancer; and

a volatile solvent,

wherein the penetration enhancer is selected from terpenes, terpenoids, essential oils, pyrrolidones, azones, sulfoxides, amides, alcohols, glycols, glycerides, amino acid derivatives, phospholipids, surfactants, and fatty acids and esters thereof having the formula I a or I b :

R 1 —C(═O)—O—H  I a

or

R 2 —C(═O)—O—R 3   I b

wherein:

R 1 is selected from a straight chain, branched, or cyclic-containing alkyl group or substituted alkyl group having 8 to 20 carbons, and a straight chain, branched, or cyclic-containing alkenyl group or substituted alkenyl group having 8 to 20 carbons;

R 2 is selected from a straight chain, branched, or cyclic-containing alkyl group or substituted alkyl group having 8 to 20 carbons, and a straight chain, branched, or cyclic-containing alkenyl group or substituted alkenyl group having 8 to 20 carbons; and

R 3 is selected from lower alkyl, lower alkenyl, a straight chain, branched, or cyclic-containing alkyl group or substituted alkyl group having 6 to 14 carbons, and a straight chain, branched, or cyclic-containing alkenyl group or substituted alkenyl group having 6 to 14 carbons; and

the substituted alkyls or substituted alkenyls have from 1 to 4 substituents selected from hydroxy, halo, oxo, alkoxy, and amino; and

wherein, when applied to the skin, the composition provides an in vivo transdermal flux of estrogen of about 0.03 to about 0.3 μg/cm 2 per hour.

2 . The transdermal estrogen spray of claim 1 , wherein the estrogen is estradiol.

3 . The transdermal estrogen spray of claim 1 , wherein the penetration enhancer is selected from the groups consisting of terpenes, terpenoids, essential oils, pyrrolidones, azones, fatty acids, fatty acid esters, sulfoxides, amides, alcohols, glycols and glycerides, amino acid derivatives, phospholipids, and surfactants.

4 . The transdermal estrogen spray of claim 3 , wherein the penetration enhancer is a fatty acid or a fatty acid ester.

5 . The transdermal estrogen spray of claim 4 , wherein the penetration enhancer is selected from a compound having the formula I a or I b :

R 1 —C(═O)—O—H  I a

or

R 2 —C(═O)—O—R 3   I b

wherein:

R 1 is selected from a straight chain, branched, or cyclic-containing alkyl group or substituted alkyl group having 8 to 20 carbons, and a straight chain, branched, or cyclic-containing alkenyl group or substituted alkenyl group having 8 to 20 carbons;

R 2 is selected from a straight chain, branched, or cyclic-containing alkyl group or substituted alkyl group having 8 to 20 carbons, and a straight chain, branched, or cyclic-containing alkenyl group or substituted alkenyl group having 8 to 20 carbons; and

R 3 is selected from lower alkyl, lower alkenyl, a straight chain, branched, or cyclic-containing alkyl group or substituted alkyl group having 6 to 14 carbons, and a straight chain, branched, or cyclic-containing alkenyl group or substituted alkenyl group having 6 to 14 carbons; and

the substituted alkyls or substituted alkenyls have from 1 to 4 substituents selected from hydroxy, halo, oxo, alkoxy, and amino.

6 . The transdermal estrogen spray of claim 3 , wherein the penetration enhancer is selected from the group consisting of butylated hydroxyanisole, 2-phenoxyethanol, thymol, menthol, menthone, cineole, isopropyl myristate, glyceryl monolaurate, glyceryl monostearate, glyceryl monooleate, oleic acid, oleyl alcohol, methyl laurate, sorbitan monooleate, lauryl lactate, and lauryl alcohol.

7 . The transdermal estrogen spray of claim 1 , wherein the solvent is selected from ethanol and isopropanol.