CC12 – Drug distribution

CC12. Drug distribution is the reversible passage of drug between tissues, organs and compartments.

12.1. Drug distribution occurs initially in the central compartment (plasma and highly perfused tissues) before distribution into peripheral

compartments (poorly perfused tissues).

12.2. Drug distribution occurs primarily through passive diffusion and is influenced by the physicochemical characteristics of the drug (e.g., molecular size, partition coefficient and ionisation).

12.3. Drug distribution is influenced by anatomical and physiological factors (e.g., local pH, blood flow and transport mechanisms) and by disease processes such as inflammation.

12.4. Drug distribution is influenced by the degree of reversible binding to proteins in the plasma; only unbound (free) drug can distribute into tissues.