Relative bioavailability of danazol in dogs from liquid-filled hard gelatin capsules.

Danazol was dissolved in non-aqueous mixtures containing either polyethylene glycol 400 or polysorbate 80, and filled into hard gelatin capsules at 50 mg concentrations. The bioavailability of these formulations was compared with commercial danazol capsules in a two-way crossover study using young female beagle dogs. Both formulations showed greater oral bioavailability when compared with either the 100 or 200 mg commercial brand of danazol. The bioavailability of the polyethylene glycol 400 and polysorbate 80 formulations was enhanced 3.7 and 15.8 times, respectively, when compared at the 100 mg dose level.