Drug metabolism

Question 1

Phase I biotransformation processes

Answer 1

• Dehydrogenation
• Epoxidation
• Dealkylation
• Hydroxylation
• Monohydroxylation of aromatics

Question 2

What is an enzyme inducer? (give examples)

Answer 2

A drug that activates enzyme via binding to them and therefore increase the metabolism.
Enzyme inducers: Rifampicin, Phenytoin

Question 3

What is an enzyme inhibitor and give examples

Answer 3

Drugs that decrease the metabolic activity of CYP450 by binding onto pockets on the surface of the enzyme.
Examples: Erythromycin, Omeprazole, Azoles

Question 4

How are compounds made easier to excrete ?

Answer 4

They are easier to excrete when they are polar and water soluble. Compounds will usually under go conjugation, oxidation and reduction during phase I and phase II of biotransformation resulting in a more polar compound.

Question 5

Phase II biotransformation processes

Answer 5

Conjugation - The adding of molecules to a compound.
* Acetylation
* Methylation
* Sulfation
* Glutathionylation
* Glucuronidation