Drug Metabolism

Question 1

Mention 5 consequence of metabolism ?

Answer 1

1. Pharmacological inactivation
2. Bioactivation or toxicological activation
3. Pharmacological activation
4. Change in pharmacological activity
5. Lethal synthesis

Question 2

Major organ of drug bio transformation?

Answer 2

Liver

Question 3

Give an example of a drug that undergoes non enzymatic metabolism and explain how ?

Answer 3

Atracurium : through molecular re-arrangement

Question 4

Microsomal enzymes activity requires?

Answer 4

NADPH and oxygen

Question 5

Microsomal enzymes are located where ?

Answer 5

Smooth endoplasmic reticulum

Question 6

Non Microsomal enzymes undergoes all phase 2 reactions except?

Answer 6

Glucoronidation

Question 7

Functionalization reaction is what phase of metabolism ?

Answer 7

Phase 1

Question 8

How many p450 enzymes are identified in human liver microsomes ?

Answer 8

15

Question 9

Mention 2 examples of drugs that undergoes auto induction?

Answer 9

Carbamazepine and rifampicin

Question 10

Mention 5 clinical importance of enzyme induction?

Answer 10

1. Decease plasma level and therapeutic effect of a drug
2. Reduce half life of a drug
3. Reduce potency and efficacy of a drug
4. Increase change of drug interactions
   5.enhance drug tolerance
5. Increase drug toxicity

Question 11

How does propranolol reduce the rate of metabolism of lignocaine ?

Answer 11

By reducing hepatic blood flow

Question 12

Mention the 3 major factors affecting drug metabolism ?

Answer 12

1. Physicochemical properties of drugs
2. Chemical factors
3. Biological factors

Question 13

Explain how sex affect drug metabolism ?

Answer 13

Metabolism is higher in males due to high GFR

Question 14

Explain the effect of of age in drug metabolism ?

Answer 14

Metabolism reduce with age cause of reduction in liver mass and liver blood flow which leads to reduction in first pass metabolism which lead to higher absorption but lower metabolism

Question 15

Mention two properties of non Microsomal enzymes ?

Answer 15

1. Non inducible
2. May show genetic variation