Drug Interactions: drug-supplement

Question 1

St. John’s Wort and CYP3A4 Substrates

Answer 1

• increases the activity of CYP3A4 enzyme (which leads to the deactivations of drugs that are substrates of CYP3A4)
• enzyme is important since its involved in the metabolism of app. 50% of all drugs
• ex: oral contraceptives, carbamazepine, colchicine

Question 2

Garlic and CYP3A4 Substrates

Answer 2

induces CYP3A4

Question 3

Cations and Levothyroxine, Quinolones, Tetracyclines & Bisphosphonates

Answer 3

may form insoluble chelate (bind to) complexes with drugs and substantially reduce their bioavailability

• only polyvalent cations

Question 4

Ginkgo and NSAIDs, Anticoagulants, or Anti-platelets

Answer 4

risk of bleeding is increased

Question 5

Dong Quai and NSAIDs, Anticoagulants, or Anti-platelets

Answer 5

increases the risk of bleeding when taken with other drugs that inhibit blood clotting

Question 6

Fish Oil and NSAIDs, Anticoagulants, or Anti-platelets

Answer 6

doses > 3g/day, fish oil can increase risk of bleeding