Drug delivery methods predominantly rely upon the inherent nature of intended medicinal/therapeutic product, other than this; delivery systems may accommodate for differing medical and physical conditions of patients and users.
Delivery systems revolve around intended medicine, route of administration and medium of administration. They modify and enhance the release quality, absorption and distribution, and eventual elimination to improve overall product safety and efficiency.
These systems are, by definition, heavily reliant on the route of administration. Facilitating optimum and precise drug release by any process (such as by absorption, diffusion or injection), typical routes of administration include oral, transdermal or topical, inhalation, and injection routes.