Question

A molecular is injected into the right basilic vein. It is visible on x-ray in the bile and is used to visualize the biliary system for diagnostic study. Trace the molecule from injection to its exit from the body.

Answer 1

When a drug is administered it undergoes 4 stages in the body they are

Absorption

Distribution

Metabolism

Excretion

Drug absorption is influenced by the route of administration, physicochemical properties etc. Drug must be in solution to be absorbed. Drug given intravenously enters directly in the circulation.

After absorption, it is carried through the body for distribution. Drug is distributed throughout the body including target organ and other organs. It moves from the bloodstream to the site of receptors in the tissues and intercellular fluid.

Once the drug is get distributed next step is metabolism. Here the drug begins to breakdown. Small molecule drug metabolism takes place in the liver by cytochrome P450 enzyme and convert the drug into metabolites. This enzymatic breakdown makes the drug easier to be eliminated.

The final phase of the drug in the body is excretion. Drug and their metabolites exit the body by this excretion, usually through kidney or focus.

A molecule that injected into the right basilic vein absorbed rapidly into the circulation. After the absorption, the drug distribution takes place. After distribution the drug undergoes metabolism. After metabolism, the drug and their metabolites excreted in the bile. Then the drug is reabsorbed into the circulation.,From the intestine, the drug eliminates through fecus.