Novel iontophoretic drug delivery of estradiol with alendronate for osteoporosis treatment

Alendronate and estradiol are potential molecules for the treatment of osteoporosis but their use is limited by lower skin permeation and first-pass metabolism respectively. To develop a combinatorial dosage regimen of alendronate and estradiol and enhance skin permeation through iontophoresis for the treatment of osteoporosis. The alendronate and estradiol-containing gel system were developed using carbopol-940 and triethanolamine as independent variables while viscosity and ex vivo permeation as dependent variables. The formulated gel was evaluated for viscosity, pH and ex vivo permeation study with and without iontophoresis. A permeation study was performed on rat abdominal skin. The viscosities for the developed formulations were found to be in the range of 945 cp-1298 cp, The pH of the formulation was found to be 7.4 which is ideal for the ionization of most drugs. Ex vivo permeation ranged from 79.99 to 99.89%. The permeation of both drugs was found to be increased upon application of DC (0.25, 0.50, 0.75 mA/cm2). The maximum percentage of permeation was found to be 99.89% (F3 batch). The skin permeation of alendronate and estradiol was enhanced by the novel formulation using iontophoresis.