What is the Origin of Vehicle Clearance?

This term is rooted in pharmacokinetics and pharmaceutical formulation science, where 'clearance' generally refers to the elimination of a substance from the body or a specific site. Applied to topical delivery, it specifically addresses the fate of the carrier substance after the active hormone has been released and absorbed. Understanding vehicle clearance is vital for designing safe and patient-friendly transdermal products.

What is the Mechanism of Vehicle Clearance?

The clearance mechanism depends heavily on the physical properties of the vehicle, such as its volatility, viscosity, and solubility. Volatile solvents, like ethanol in gels, clear rapidly through evaporation from the skin surface. Non-volatile components, such as

Vehicle Clearance ∞ Area

Vehicle Clearance

Meaning

Vehicle Clearance, in the context of topical drug delivery, refers to the rate and mechanism by which the non-active components of a topical formulation, known as the vehicle or excipients, are removed from the skin surface. This is a crucial factor in transdermal pharmacology as the remaining vehicle residue can influence subsequent drug absorption, skin irritation, and patient adherence. Effective clearance is desired to minimize the potential for local adverse reactions.