Selected HMG Co-A Reductase Inhibitors/Efavirenz
This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.
Medical warning:
Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
Efavirenz may speed up how quickly your liver processes your cholesterol medicine.
What might happen:
The amount of cholesterol medicine in your blood may decrease and it may not work as well.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. Your doctor may want to check your cholesterol level to see if your cholesterol medicine is working. Your doctor may want to change the dosage of your cholesterol medicine while you are taking efavirenz or if you stop taking efavirenz.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
References:
1.Gerber JG, Rosenkranz SL, Fichtenbaum CJ, Vega JM, Yang A, Alston BL, Brobst SW, Segal Y, Aberg JA. Effect of efavirenz on the pharmacokinetics of simvastatin, atorvastatin, and pravastatin: results of AIDS Clinical Trials Group 5108 Study. J Acquir Immune Defic Syndr 2005 Jul 1; 39(3):307-12.
2.Sustiva (efavirenz) US prescribing information. Bristol-Myers Squibb Company August, 2012.
3.Atripla (efavirenz/emtricitabine/tenofovir disoproxil fumarate) US prescribing information. Gilead Sciences, Inc. June, 2012.





