Can currently available drugs for erectile dysfunction be re-formulated to achieve rapid effect?
Author: Janette Park, Afua Agyemang, Moses S. S. Chow
Category: Pharmacy
Abstract:
Currently available drugs (sildenafil, tadalafil, vardenafil) for erectile dysfunction (ED) are only approved for oral administration. The time to achieve maximum plasma drug concentration (Tmax) and onset of effect following the oral administrations is usually around 30-60 min. Sublingual/intranasal administration can offer convenient and more rapid Tmax. The present article provides a review of the chemical/physical properties of the 3 drugs as well as anatomical and physiological characteristics relevant to sublingual/intranasal drug delivery. In addition, new formulations reported in the literature for such delivery are assessed for suitability to human administration. Based on our review, we believe that intranasal delivery of these drugs is more likely to be successful due to the large surface area of absorption mucosa as well as amount of drug needed to achieve therapeutic effect. An appropriate solubilizing vehicle as well as a pH of 4-7 that can allow rapid absorption will be crucial for rapid intranasal delivery of these drugs.
