Sildenafil sublingual spray formulations

1. A sublingual spray formulation comprising:

a. from about 5% w/w to about 35% w/w sildenafil or a salt thereof;

b. from about 0.1% w/w to about 60% w/w of at least one pharmacologically acceptable polar solvent selected from the group consisting of purified water, ethanol, and polyethylene glycol 400;

c. an excipient selected from about 0.1% w/w to about 50% w/w glycerol, from about 0.1% w/w to about 50% w/w propylene glycol and a combination thereof;

d. from about 0.1% w/w to about 60% w/w of at least one acid selected from the group consisting of an inorganic acid and an organic acid; and

e. a permeation enhancer comprising caprylic acid,

wherein the permeation enhancer enhances sublingual delivery of sildenafil or a salt thereof and wherein % w/w is of the total formulation.

2. The formulation of claim 1 wherein the acid is diluted hydrochloric acid.

3. The formulation of claim 1 wherein the excipient is from about 5% w/w to about 30% w/w glycerol.

4. The formulation of claim 1 comprising from about 0.1% w/w to about 50% w/w water.

5. The formulation of claim 1 comprising from about 10% w/w to about 60% w/w ethanol.

6. The formulation of claim 1 wherein the excipient is from about 5% w/w to about 30% w/w propylene glycol.

7. The formulation of claim 1 wherein the formulation is propellant free.

8. The formulation of claim 1 wherein the sildenafil is a pharmaceutically acceptable salt selected from the group consisting of citrate, hydrochloride, halide, sulfate, phosphate, acetate, maleate, succinate, ascorbate, carbonate, mesylate and lactate.

9. The formulation of claim 1 further comprising an antioxidant and/or stabilizer, sweetener, sweetness enhancer, pH modifier, flavoring agent, permeation enhancer, preservative, or a combination thereof.

10. The formulation of claim 9 comprising an antioxidant and/or stabilizer selected from the group consisting of ascorbyl palmitate, ascorbic acid, alpha tocopherol, butylated hydroxytoluene, buthylated hydroxyanisole, cysteine HCl, citric acid, ethylenediamine tetra acetic acid (EDTA), methionine, sodium citrate, sodium ascorbate, sodium thiosulfate, sodium metabisulfite, sodium bisulfate, propyl gallate, glutathione and thioglycerol.

11. The formulation of claim 9 wherein the permeation enhancer further comprises a second compound selected from the group consisting of menthol, limonene, carvone, methyl chitosan, polysorbates, sodium lauryl sulfate, glyceryl oleate, caproic acid, enanthic acid, pelargonic acid, capric acid, undecylenic acid, lauric acid, myristic acid, palmitic acid, oleic acid, stearic acid, linolenic acid, arachidonic acid, benzethonium chloride, benzethonium bromide, benzalkonium chloride (BKC), cetylpyridium chloride, edetate disodium dihydrate, sodium desoxycholate, sodium deoxyglycolate, sodium glycocholate, sodium caprate, sodium taurocholate, sodium hydroxybenzoyal amino caprylate, dodecyl dimethyl aminopropionate, L-lysine, glycerol oleate, glyceryl monostearate, citric acid, peppermint oil and a combination thereof.

12. The formulation of claim 11 , wherein the permeation enhancer comprises menthol as the second compound.

13. The formulation of claim 1 , wherein the caprylic acid is at a concentration from about 0.1% w/w to about 20% w/w.

14. The formulation of claim 13 , wherein the caprylic acid is at a concentration from about 0.1% w/w to about 5% w/w.

15. A propellant free sublingual spray formulation comprising:

a. from about 5% w/w to about 20% w/w sildenafil or a salt thereof;

b. from about 35% w/w to about 55% w/w ethanol;

c. from about 1% w/w to about 30% w/w water;

d. an excipient selected from the group consisting of from about 5% w/w to about 30% w/w glycerol, from about 5% w/w to about 30% w/w propylene glycol, and from about 5% w/w to about 30% w/w polyethylene glycol 400; and

e. from about 0.1% w/w to about 60% w/w diluted hydrochloric acid; and

f. a permeation enhancer comprising caprylic acid,

wherein % w/w is of the total formulation.

16. A propellant free sublingual spray formulation comprising:

a. about 8% w/w sildenafil or a salt thereof;

b. about 40% w/w ethanol;

c. about 10% w/w glycerol;

c. about 26% w/w water;

d. about 12% w/w diluted hydrochloric acid; and

e. a permeation enhancer comprising 0.5% w/w menthol and 2% w/w caprylic acid,

wherein % w/w is of the total formulation.

17. A method of treating sexual dysfunction in men comprising administering the formulation of claim 1 to a patient in need thereof.

18. The method of claim 17 , wherein the spray pumps deliver about 50 to 400 of the formulation of claim 1 under the tongue.

19. A method of treating pulmonary arterial hypertension in a human comprising administering the formulation of claim 1 to a patient in need thereof.