A 64-year-old client takes atorvastatin 40 mg orally each ev… | MyMerci
Medical EmergenciesPA
Question
A 64-year-old client takes atorvastatin 40 mg orally each evening. The provider writes a new order for clarithromycin 500 mg orally twice daily for 10 days for a community-acquired respiratory infection. Which action by the nurse is most appropriate?
1Withhold the atorvastatin for the entire 10-day antibiotic course and resume it 3 days after the clarithromycin is finished, documenting the decision in the medical record without contacting the prescriber.
2Administer the atorvastatin concurrently with the clarithromycin, scheduling them at separate times to minimize potential gastrointestinal upset but taking no additional action regarding the drug interaction.
3Contact the prescriber and suggest switching the antibiotic to azithromycin because it lacks significant CYP3A4 inhibition, while continuing to administer atorvastatin and the first dose of clarithromycin.
4Notify the prescriber about the atorvastatin–clarithromycin CYP3A4 interaction and ask whether atorvastatin should be temporarily held during the antibiotic course or whether the antibiotic should be changed.✓ Correct answer
Explanation
Atorvastatin + clarithromycin — CYP3A4 interaction Atorvastatin (also simvastatin·lovastatin) is a CYP3A4 substrate. Clarithromycin is a strong CYP3A4 inhibitor, and concurrent use raises atorvastatin plasma levels several-fold, increasing the risk of myopathy and rhabdomyolysis. Per FDA labeling and clinical guidelines, options are: (1) avoid the combination and use a non-CYP3A4 statin (pravastatin·rosuvastatin·pitavastatin) or non-interacting macrolide (azithromycin), (2) temporarily hold atorvastatin during the short antibiotic course, or (3) reduce atorvastatin dose with close monitoring. The nurse must notify the prescriber for clarification before administering — never assume, never permanently discontinue without an order, never double the dose. Other CYP3A4 inhibitors to remember with statins: erythromycin·diltiazem·verapamil·azole antifungals (ketoconazole·itraconazole·fluconazole)·protease inhibitors·cyclosporine·grapefruit juice. Azithromycin is the macrolide of choice when concurrent use is needed.
In-depth explanation
Clinical reasoning summary Atorvastatin + clarithromycin — CYP3A4 interaction Atorvastatin (also simvastatin·lovastatin) is a CYP3A4 substrate. Clarithromycin is a strong CYP3A4 inhibitor, and concurrent use raises atorvastatin plasma levels several-fold, increasing the risk of myopathy and rhabdomyolysis. Per FDA labeling and clinical guidelines, options are: (1) avoid the combination and use a non-CYP3A4 statin (pravastatin·rosuvastatin·pitavastatin) or non-interacting macrolide (azithromycin), (2) temporarily hold atorvastatin during the short antibiotic course, or (3) reduce atorvastatin dose with close monitoring. The nurse must notify the prescriber for clarification before administering — never assume, never permanently discontinue without an order, never double the dose. Other CYP3A4 inhibitors to remember with statins: erythromycin·diltiazem·verapamil·azole antifungals (ketoconazole·itraconazole·fluconazole)·protease inhibitors·cyclosporine·grapefruit juice. Azithromycin is the macrolide of choice when concurrent use is needed.