L9 - Metabolism Of Analgesics

Question 1

2 metabolism stages

Answer 1

Phase 1- activation by oxidation reduction and hydrolysis

Phase 2- conjugation to make polar molecules

Question 2

Paracetamol metabolised by

Answer 2

Cns- active
Cyp450 2E1- toxic/inactive
sulfation - inactive
glucoronidation- inactive

Question 4

Codeine metabolism

Answer 4

Cyp450 2D6- active
Cup4503A4- inactive

Question 5

Where is Cyp450 found

Answer 5

Mitochondria or endoplasmic reticulum

Question 6

Polymorphism in terms of CYP450

Answer 6

There are many different forms, each encoded by a specific gene. Each catalyse different classes of drugs. This causes drug-drug interactions.

Question 7

How are drugs deactivated by cyp

Answer 7

Either directly or by facilitated excretion from the body

Question 8

Drugs which effect cyp activity also effect…

Answer 8

Metabolic rate, plasma conc and therapeutic effects of any co administered drugs

Question 10

Why is genetic variation important to consider when prescribing analgesics

Answer 10

Some patients are deficient in genes which encode and produce cyp metabolising enzymes