Distribution of drug and Tissue perfusion

                 B. Organ or tissue perfusion

Lipid soluble drugs enter the highly perfused tissues such as lungs, kidney, liver, heart, brain rapidly. The extent to which a drug is distributed in to the tissue or organ depends upon site of the tissue and the partition co-efficient of the drug.

Fat is less perfused, made up of the adipose tissue. If the lipid soluble drug is given to the person having more adipose tissue or fat (obes), then the drug is stored in to the fat & it acts as reservoir of the drug.

Bones are absorbed some drugs from blood circulation, like tetracycline (chelate forming with Ca⁺² , lead etc. from which the drug is released slowly & causing prolonged released effect.