Which of the following is the two most common routes of administration?

• A. Inhalation and Subcutaneous
• B. Oral and Topical
• C. Rectal and Vaginal
• D. Intravenous and Intramuscular

Answer: (B)

Most medications are given by mouth or applied to the skin because these routes are simple, non-invasive, and suitable for a wide range of drugs and patients. Oral administration—through pills, capsules, or liquids—allows convenient, self-administration at home and provides systemic effects when the drug needs to act throughout the body. Topical administration—creams, ointments, gels, or patches—delivers treatment directly to the skin or mucous membranes, ideal for localized conditions and with typically lower risk of widespread side effects. Other routes, such as injections, inhalation, or those through the rectal or vaginal passages, are used for specific situations and often require more training, devices, or particular patient factors. Because of their broad applicability and ease of use, oral and topical routes are the most common.