Examples of Enzyme Inducers and Inhibitors in Drug Metabolism

📚 Quick Study Guide

• 🧪 Enzyme inducers increase the synthesis or activity of enzymes, leading to faster drug metabolism.
• 💊 Enzyme inhibitors decrease the activity of enzymes, leading to slower drug metabolism and potentially increased drug levels.
• 🍎 Certain foods and herbal remedies can also act as enzyme inducers or inhibitors.
• 🧬 Cytochrome P450 (CYP) enzymes are a major group of enzymes involved in drug metabolism.
• 🔢 Induction can decrease drug efficacy; inhibition can increase drug toxicity.
• 💡 Monitoring drug levels is important when enzyme inducers or inhibitors are involved.
• ⏱️ The effect of enzyme inducers and inhibitors can take days or weeks to manifest.

Practice Quiz

1. Which of the following is an example of an enzyme inducer?

1. A) Ketoconazole
2. B) Erythromycin
3. C) Rifampin
4. D) Grapefruit juice

2. Which of the following is an example of an enzyme inhibitor?

1. A) Phenytoin
2. B) Carbamazepine
3. C) Cimetidine
4. D) St. John's Wort

3. Enzyme inducers primarily affect drug metabolism by:

1. A) Blocking drug absorption
2. B) Increasing enzyme synthesis
3. C) Decreasing enzyme activity
4. D) Increasing drug excretion

4. Enzyme inhibitors primarily affect drug metabolism by:

1. A) Increasing enzyme synthesis
2. B) Decreasing drug excretion
3. C) Decreasing enzyme activity
4. D) Blocking drug receptors

5. Which of the following Cytochrome P450 enzymes is most commonly involved in drug metabolism?

1. A) CYP1A1
2. B) CYP2D6
3. C) CYP3A4
4. D) CYP2C9

6. What is a potential consequence of taking a drug that is metabolized by CYP3A4 with an enzyme inhibitor of CYP3A4?

1. A) Decreased drug efficacy
2. B) Increased risk of drug toxicity
3. C) Faster drug metabolism
4. D) Reduced drug absorption

7. St. John's Wort is a well-known:

1. A) CYP2D6 Inhibitor
2. B) CYP3A4 Inducer
3. C) CYP2C9 Inhibitor
4. D) CYP1A2 Inducer

Click to see Answers

1. Answer: C) Rifampin
2. Answer: C) Cimetidine
3. Answer: B) Increasing enzyme synthesis
4. Answer: C) Decreasing enzyme activity
5. Answer: C) CYP3A4
6. Answer: B) Increased risk of drug toxicity
7. Answer: B) CYP3A4 Inducer