Science of drug delivery has achieved tremendous milestones in the last few decades. Emergence of novel drug delivery techniques and the most popular nanotechnology directed the drug delivery to another level. Without any doubt, present technology holds the proficiency to approach even the intercellular targets. Between all these success auras, there lies wads of giant challenges. One such challenge is delivering the molecule directly to the blood stream. Parenteral route is considered as the most effective route for delivering active pharmaceutical substances, but is associated with major disadvantages of painful drug delivery. Modern drug delivery suggests several approaches to outstrip this painful phenomenon. In the present article, we represent a new systematic vision to understand the ability and desirability of mucosal sites to achieve painless drug delivery. Human mucosa presents supreme proximity to the blood circulation that one can even observe with naked eye. Advances in drug delivery provide numerous approaches to exploit the mucosa for systemic reach. However, the revolutionary success is still unapproachable, with an understandable reason of associated complexities and challenges. This manuscript summarizes the significance of each mucosal site, on the basis of anatomical-physiological grounds. Particular attention is given to rationalize the selection of disease and a suitable drug delivery approach for its treatment.
Keywords: Systemic delivery; drug delivery; mucosal sites; non-invasive; painless.