1. A free drug particulate form of a compound having a formula and pharmaceutically acceptable salts and solvates thereof, comprising particles of the compound wherein at least 90% of the particles have a particle size of less than about 40 microns. 2. The free drug particulate form of claim 1 wherein at least 90% of the particles have a particle size of less than about 25 microns. 3. The free drug particulate form of claim 1 wherein at least 90% of the particles have a particle size of less than about 15 microns. 4. The free drug particulate form of claim 1 wherein at least 90% of the particles have a particle size of less than about 10 microns. 5. A pharmaceutical composition comprising the free drug particulate form of claim 1 and one or more pharmaceutically-acceptable carriers, diluents, or excipients. 6. The pharmaceutical composition of claim 5 wherein the free drug is entirely in particulate form. 7. A method of treating sexual dysfunction in a patient in need thereof, which comprises administering to the patient a therapeutically effective amount of a composition comprising the free drug particulate form of claim 1 and one or more pharmaceutically-acceptable carriers, diluents, or excipients. 8. The method of claim 7 wherein the sexual dysfunction is male erectile dysfunction. 9. The method of claim 7 wherein the sexual dysfunction is female sexual arousal disorder. 10. A pharmaceutical composition comprising: (a) a free drug form of a compound having the formula and pharmaceutically-acceptable salts and solvates thereof, and (b) one or more pharmaceutically-acceptable carriers, diluents, or excipients, wherein the composition exhibits a Cmax of about 180 to about 280 micrograms/liter or an AUC (0-24) of about 2280 to about 3560 microgram-hour/ liter, measured using a 10 milligram dose of the compound. 11. The composition of claim 10 wherein the composition exhibits a Cmax of about 180 to about 280 micrograms/liter and an AUC (0-24) of about 2280 to about 3560 microgram-hour/liter. 12. A pharmaceutical composition comprising: (a) a compound having the formula and pharmaceutically-acceptable salts and solvates thereof, and (b) one or more pharmaceutically acceptable carriers, diluents, or excipients, wherein the composition exhibits a Cmax of about 180 to about 280 micrograms/liter and an AUC (0-24) of about 2280 to about 3560 micrograms-hour/liter, measured using a 10 milligram dose of the compound. 13. A pharmaceutical composition comprising: (a) a free drug form of a compound having the formula and pharmaceutically acceptable salts and solvates thereof, wherein at least 90% of the particles have a particle size of less than about 10 microns, and (b) one or more pharmaceutically-acceptable carriers, diluents, or excipients, and bioequivalent compositions thereof. 14. A method of manufacturing the free drug particulate form of claim 1 comprising: comminuting the solid free form of the compound to provide particles of the compound wherein at least 90% of the particles have a particle size of less than about 40 microns. 15. A method of manufacturing a pharmaceutical composition including the free drug particulate form of claim 1 comprising: (a) comminuting the solid free form of the compound to provide particles of the compound wherein at least 90% of the particles have a particle size of less than about 40 microns; and (b) admixing the particles with one or more pharmaceutically acceptable carriers, diluents, or excipients. 16. A pharmaceutical composition prepared by admixing particles of a compound having a formula or a pharmaceutically-acceptable salt or solvate thereof, with one or more pharmaceutically-acceptable carrier, diluent, or excipient, wherein the particles of the compound have a d 90=40 or less. 17. Use of particles of a free form of a compound having a formula wherein at least 90% of the particles have a particle size of less than about 40 microns, for the manufacture of a medicament for the treatment of male erectile dysfunction. 18. Use according to claim 17 wherein the sexual dysfunction is male erectile dysfunction. 19. Use according to claim 17 wherein the sexual dysfunction is female sexual arousal disorder. 20. Use of particles of a free form of a compound having a formula which exhibits a Cmax of about 180 to about 280 micrograms/liter and an AUC (0-24) of about 2280 to about 3560 micrograms-hour/liter, measured using an 10 milligram dose of the compound, for the manufacture of a medicament for the treatment of sexual dysfunction. 21. Use according to claim 20 wherein the sexual dysfunction is male erectile dysfunction. 22. Use according to claim 20 wherein the sexual dysfunction is female sexual arousal disorder. 23. Use according to any one of claims 17-22 wherein the medicament is prepared for oral administration to a maximum daily dose of 20 mg/day.