Drug Distribution

Question 1

3 primary process of drug distribution

Answer 1

Absorption, distribution and excretion.

Question 2

First pass hepatic elimination

Answer 2

Orally administered drugs undergo biotransformation in the liver leading to a reduction in the amount of active drug reaching systemic circulation.

Question 3

Two biological barriers drugs must overcome so reach circulation

Answer 3

GI-tract barrier (intestinal epithelium) and blood-brain barrier (CNS endothelia).

Question 4

Primary methods of which drugs use to traverse membranes

Answer 4

Gradient diffusion, carrier transport, vesicular transport and receptor meidated endocytosis.

Question 5

Phase 1 and 2 biotransformations

Answer 5

Phase 1: Oxidation, reduction, hydrolysis
Phase 2: Conjugation and acidifying.

Question 6

Why is drug binding to plasma proteins crucial in pharmacokinetics?

Answer 6

It alters concentration of free drug in the blood influencing it’s effect.

Question 7

What is the role of molecular mass in the renal excretion of drugs?

Answer 7

Molecular mass of less than 5,000 Da generally pass through vascular walla into glomerular capillaries.