Herbal Medicine & Drug Interaction Challenge: 150
Questions with Detailed Answers and Rationales
2025/2026
1. A patient taking warfarin asks about using ginkgo biloba to
improve memory. What is the nurse’s best response?
Answer: Ginkgo biloba may increase the risk of bleeding when
taken with warfarin.
Rationale: Ginkgo inhibits platelet aggregation, which can
potentiate anticoagulant effects and increase bleeding risk.
2. Which herbal supplement is commonly used to reduce mild
anxiety and promote sleep?
Answer: Valerian root
Rationale: Valerian root acts on GABA receptors, promoting
sedation and reducing anxiety.
3. A patient on digoxin wants to start taking St. John’s wort for
depression. What is the concern?
Answer: St. John’s wort can reduce digoxin effectiveness.
Rationale: St. John’s wort induces CYP3A4 and P-glycoprotein,
decreasing digoxin plasma levels and therapeutic effect.
4. Garlic supplements may have which effect when combined with
antiplatelet therapy?
Answer: Increased risk of bleeding
Rationale: Garlic can inhibit platelet aggregation and enhance the
effects of anticoagulants or antiplatelet drugs.
5. Which herbal supplement is often used to improve cognitive
function in older adults?
, Answer: Ginkgo biloba
Rationale: Ginkgo biloba may enhance blood flow to the brain and
improve memory, but caution is needed with anticoagulants.
6. What is a major safety concern when taking kava kava?
Answer: Hepatotoxicity
Rationale: Kava kava has been associated with liver damage,
including hepatitis and liver failure.
7. A patient taking an MAOI asks about using tyramine-rich herbal
supplements. What advice should the nurse provide?
Answer: Avoid herbal supplements high in tyramine.
Rationale: High-tyramine supplements can precipitate
hypertensive crisis in patients on MAOIs.
8. Echinacea is commonly used for which purpose?
Answer: To prevent or treat common colds
Rationale: Echinacea may stimulate the immune system, reducing
the duration and severity of upper respiratory infections.
9. A patient using chamomile tea daily is also on warfarin. What risk
should the nurse monitor?
Answer: Increased risk of bleeding
Rationale: Chamomile contains coumarin-like compounds that can
enhance anticoagulant effects.
10. Saw palmetto is most commonly used for which condition?
Answer: Benign prostatic hyperplasia (BPH)
Rationale: Saw palmetto may improve urinary symptoms in men
with BPH, though it may also have mild anticoagulant effects.
11. A patient reports using high doses of green tea while taking
a beta-blocker. What is the potential concern?
Answer: Reduced efficacy of the beta-blocker
, Rationale: Green tea contains catechins that may interfere with
absorption and metabolism of certain medications.
12. Which herbal supplement is associated with serotonin
syndrome when combined with SSRIs?
Answer: St. John’s wort
Rationale: St. John’s wort can increase serotonin levels and, when
combined with SSRIs, may lead to serotonin syndrome.
13. A patient wants to take ginger to help with nausea while on
anticoagulants. What is the nurse’s recommendation?
Answer: Use caution, as ginger may increase bleeding risk
Rationale: Ginger can inhibit platelet aggregation and may
potentiate anticoagulant therapy.
14. Milk thistle is primarily used for which purpose?
Answer: Liver protection
Rationale: Milk thistle contains silymarin, which may protect
hepatocytes and support liver function.
15. A patient on insulin asks about taking ginseng. What should
the nurse monitor?
Answer: Blood glucose levels
Rationale: Ginseng may lower blood glucose and can increase the
risk of hypoglycemia in patients on insulin or oral hypoglycemic
agents.
16. Which herbal supplement can reduce the effectiveness of
oral contraceptives?
Answer: St. John’s wort
Rationale: St. John’s wort induces liver enzymes that metabolize
contraceptive hormones, reducing efficacy.
Questions with Detailed Answers and Rationales
2025/2026
1. A patient taking warfarin asks about using ginkgo biloba to
improve memory. What is the nurse’s best response?
Answer: Ginkgo biloba may increase the risk of bleeding when
taken with warfarin.
Rationale: Ginkgo inhibits platelet aggregation, which can
potentiate anticoagulant effects and increase bleeding risk.
2. Which herbal supplement is commonly used to reduce mild
anxiety and promote sleep?
Answer: Valerian root
Rationale: Valerian root acts on GABA receptors, promoting
sedation and reducing anxiety.
3. A patient on digoxin wants to start taking St. John’s wort for
depression. What is the concern?
Answer: St. John’s wort can reduce digoxin effectiveness.
Rationale: St. John’s wort induces CYP3A4 and P-glycoprotein,
decreasing digoxin plasma levels and therapeutic effect.
4. Garlic supplements may have which effect when combined with
antiplatelet therapy?
Answer: Increased risk of bleeding
Rationale: Garlic can inhibit platelet aggregation and enhance the
effects of anticoagulants or antiplatelet drugs.
5. Which herbal supplement is often used to improve cognitive
function in older adults?
, Answer: Ginkgo biloba
Rationale: Ginkgo biloba may enhance blood flow to the brain and
improve memory, but caution is needed with anticoagulants.
6. What is a major safety concern when taking kava kava?
Answer: Hepatotoxicity
Rationale: Kava kava has been associated with liver damage,
including hepatitis and liver failure.
7. A patient taking an MAOI asks about using tyramine-rich herbal
supplements. What advice should the nurse provide?
Answer: Avoid herbal supplements high in tyramine.
Rationale: High-tyramine supplements can precipitate
hypertensive crisis in patients on MAOIs.
8. Echinacea is commonly used for which purpose?
Answer: To prevent or treat common colds
Rationale: Echinacea may stimulate the immune system, reducing
the duration and severity of upper respiratory infections.
9. A patient using chamomile tea daily is also on warfarin. What risk
should the nurse monitor?
Answer: Increased risk of bleeding
Rationale: Chamomile contains coumarin-like compounds that can
enhance anticoagulant effects.
10. Saw palmetto is most commonly used for which condition?
Answer: Benign prostatic hyperplasia (BPH)
Rationale: Saw palmetto may improve urinary symptoms in men
with BPH, though it may also have mild anticoagulant effects.
11. A patient reports using high doses of green tea while taking
a beta-blocker. What is the potential concern?
Answer: Reduced efficacy of the beta-blocker
, Rationale: Green tea contains catechins that may interfere with
absorption and metabolism of certain medications.
12. Which herbal supplement is associated with serotonin
syndrome when combined with SSRIs?
Answer: St. John’s wort
Rationale: St. John’s wort can increase serotonin levels and, when
combined with SSRIs, may lead to serotonin syndrome.
13. A patient wants to take ginger to help with nausea while on
anticoagulants. What is the nurse’s recommendation?
Answer: Use caution, as ginger may increase bleeding risk
Rationale: Ginger can inhibit platelet aggregation and may
potentiate anticoagulant therapy.
14. Milk thistle is primarily used for which purpose?
Answer: Liver protection
Rationale: Milk thistle contains silymarin, which may protect
hepatocytes and support liver function.
15. A patient on insulin asks about taking ginseng. What should
the nurse monitor?
Answer: Blood glucose levels
Rationale: Ginseng may lower blood glucose and can increase the
risk of hypoglycemia in patients on insulin or oral hypoglycemic
agents.
16. Which herbal supplement can reduce the effectiveness of
oral contraceptives?
Answer: St. John’s wort
Rationale: St. John’s wort induces liver enzymes that metabolize
contraceptive hormones, reducing efficacy.
