1. A pharmaceutical formulation comprising an active compound having the structural formula wherein said compound is provided as free drug; a water-soluble diluent; a lubricant; a hydrophilic binder selected from the group consisting of a cellulose derivative, povidone, and a mixture thereof; and a disintegrant selected from the group consisting of croscarmellose sodium, crospovidone, and a mixture thereof. 2. The formulation of claim 1 further comprising microcrystalline cellulose. 3. The formulation of claim 1 further comprising a wetting agent. 4. The formulation of claim 1 wherein the active compound is present in an amount of about 0.5% to about 10% by weight. 5. The formulation of claim 1 wherein the water-soluble diluent is selected from the group consisting of a sugar, a polysaccharide, a polyol, a cyclodextrin, and mixtures thereof. 6. The formulation of claim 3 wherein the water-soluble diluent is selected from the group consisting of lactose, sucrose, dextrose, a dextrate, a maltodextrin, mannitol, xylitol, sorbitol, a cyclodextrin, and mixtures thereof. 7. The formulation of claim 1 wherein the lubricant is present in an amount of about 0.25% to about 2% by weight. 8. The formulation of claim 1 wherein the lubricant is selected from the group consisting of talc, magnesium stearate, calcium stearate, stearic acid, colloidal silicon dioxide, calcium silicate, a starch, mineral oil, a wax, glyceryl behenate, a polyethylene glycol, sodium benzoate, sodium acetate, sodium stearyl fumarate, hydrogenated vegetable oils, and mixtures thereof. 9. The formulation of claim 1 wherein the cellulose derivative is selected from the group consisting of hydroxypropylcellulose, hydroxypropyl methylcellulose, and mixtures thereof. 10. The formulation of claim 1 wherein the disintegrant is present in an amount of about 3% to about 10% by weight. 11. The formulation of claim 2 wherein the microcrystalline cellulose is present in an amount of about 5% to about 40% by weight. 12. The formulation of claim 3 wherein the wetting agent is present in an amount of 0.1% to about 5% by weight. 13. The formulation of claim 12 wherein the wetting agent is selected from the group consisting of sodium lauryl sulfate, docusate sodium, ethoxylated castor oil, a polyglycolyzed glyceride, an acetylated monoglyceride, a sorbitan fatty acid ester, a poloxamer, a polyoxyethylene sorbitan fatty acid ester, a polyoxyethylene, a monoglyceride and ethoxylated derivatives thereof, a diglyceride and ethoxylated derivatives thereof, and mixtures thereof. 14. The formulation of claim 1 wherein the wetting agent is selected from the group consisting of sodium lauryl sulfate, polysorbate 80, and a mixture thereof. 15. The formulation of claim 1 wherein the active compound is provided as particles of a free drug wherein at least 90% of the particles have a particle size less than about 40 microns. 16. The formulation of claim 1 wherein the active compound is provided as particles of a free drug wherein at least 90% of the particles have a particle size less than about 10 microns. 17. The formulation of claim 1 comprising: (a) about 1% to about 4% by weight of the active compound; (b) about 50% to about 75% by weight lactose; (c) about 0.25% to about 2% by weight magnesium stearate; (d) about 1% to about 5% by weight hydroxypropyl cellulose; and (e) about 3% to about 10% by weight croscarmellose sodium. 18. The formulation of claim 16 further comprising about 5% to about 40% by weight microcrystalline cellulose. 19. The formulation of claim 16 further comprising about 0.1% to about 5% by weight sodium lauryl sulfate. 20. A tablet comprising the formulation of claim 1 wherein the active compound is present in an amount of about 1 to about 20 mg per tablet. 21. A tablet comprising the formulation of claim 1 wherein the active compound is present in an amount of about 5 to about 15 mg per tablet. 22. A tablet comprising the formulation of claim 1 wherein the active compound is present in an amount of about 5 mg or about 10 mg per tablet. 23. A capsule comprising a hard shell encasing the formulation of claim 1 as dry, free-flowing particles, wherein the active compound is present in an amount of about 1 to about 20 mg per capsule. 24. A method of treating sexual dysfunction in a patient in need thereof comprising administering to the patient an effective amount of a formulation of any one of claims 1 through 21.