PCEUT: Percutaneous Absorption: questions with correct answers

Percutaneous Absorption: Topical Drug Administration for Local or Systemic Effect - Answer Percutaneous absorption is the process by which drug passes into and/or through the skin after application to the surface of the skin. Equivalent terms include: • topical drug administration • dermal drug administration • transdermal drug administration Percutaneous Absorption: Topical Drug Administration for Local or Systemic Effect - Answer Topical administration of drugs is intended either for: • local effect (if specified target for the drug is the skin itself, referred to as "dermal drug delivery") - unintentional systemic drug exposure may occur, depending upon factors such as physicochemical drug properties, dosage formulation design, concentration of drug in formulation, and frequency of application • systemic effect (referred to as "transdermal drug delivery") Percutaneous Absorption: Topical Drug Administration for Local or Systemic Effect - Answer There is continued discussion about whether drugs penetrate the SC or penetrate the skin via the sweat gland, hair follicles and sebaceous glands (the so-called transappendageal route). Likelihood is that both routes are involved; however, the transappendageal route is difficult to study. - corticosteroids cross the stratum corneum relatively slowly so the thought is that the rapid clinical response is due to their passage by diffusion through the follicles How is percutaneous absorption study, quantified, and interpreted? - Answer page 3-4