RxTechExam Module 3 - Common Drug Interactions

Warfarin

Drug Interactions: NSAIDs, Antibiotics, Fish Oil, Garlic Supplements, Coenzyme 10, Vitamin K

Side Effects: Excessive Bruising / Bleeding

Contraindication: Pregnancy Category X

NSAIDs

Drug Interactions: Toxicity with Lithium or Methotrexate supplementation

Interactions: Increased risk of bleeding with Coumadin

HMG-CoA Reductase Inhibitors (statins)

Food Interaction: Grapefruit inhibits metabolism leading to muscle damage (rhabdomyolysis)

Contraindication: Pregnancy Category X

Benzodiazepines & Opioids

Drug Interaction: When taken together can cause respiratory depression

Contraindication: Pregnancy Category D (benzodiazepines)

Clopidogrel and PPIs

Drug Interaction: PPIs can reduce effectiveness of clopidogrel

Antibiotics

Drug Interaction: 1) reduced effectiveness of birth control 2) increased risk of bleeding with anticoagulants

Contraindication: Pregnancy category varies; doxycycline is D

ACE Inhibitors (ACEi)

Contraindication: Pregnancy Category D

SSRIs & SNRIs

Drug Interaction: When SSRIS or SNRIs are taken with MAOIs, can cause serotonin syndrome

Lithium

Drug Interactions: Alcohol, methotrexate, NSAIDs should be avoided

Contraindication: Pregnancy Category D