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Home > Treatment > HIV Meds Quarterly > Winter 2010 > ARV Updates
Updates to the Database of ARV Drug Interactions

The following table summarizes recent additions to the HIV InSite Database of Antiretroviral Drug Interactions. For a full description of the updates, including references to the studies from which the data were derived, go to the database, click on a specific drug name, and search for the interacting agent.

New ARV Interactions (November 2009-March 2010)
Drug OneDrug TwoClinical EffectsMechanismsManagement
Source: McNicholl I. HIV InSite Database of Antiretroviral Drug Interactions. University of California San Francisco: Center for HIV Information; 2009
DarunavirBuprenorphineInhibition of CYP 3A4 by darunavir/ritonavirNo dosage adjustment necessary
DarunavirDigoxinMonitor digoxin level and adjust digoxin dosage based on clinical signs and digoxin level
DarunavirOmeprazoleNo dosage adjustment necessary
DarunavirRifabutinInhibition of CYP 3A4 by darunavir/ritonavirNo dosage adjustment necessary; potentially could use rifabutin 150 mg QOD
DarunavirWarfarin↓ warfarin effects (eg, ↓ INR, ↑ risk of clotting)Induction of CYP 3A4 by darunavirMonitor INR and adjust warfarin as indicated
EfavirenzLevonorgestrel↓ levonorgestrel effectsInduction of levonorgestrel metabolism by efavirenzUse backup form of birth control (eg, barrier)
EtravirineClopidogrelPossibly ↓ clopidogrel effectsActivation of clopidogrel to its active metabolites may be ↓ by etravirineAvoid combination; consider alternative agents
EtravirineFluconazole↑ etravirine effectsInhibition of CYP 3A4 by fluconazoleDosage adjustment not established
EtravirineLopinavir/ritonavirPotentially ↓ etravirine effectsPotential induction of CYP 3A4, 2C9, and 2C19 by lopinavir/ritonavirNo dosage adjustment necessary
EtravirineVoriconazolePossibly ↑ etravirine effectsInhibition of CYP 3A4 by voriconazoleNo dosage adjustment necessary
FosamprenavirPosaconazole↓ posaconazole and fosamprenavir efficacyDo not coadminister
IndinavirGinsengNo dosage adjustment necessary
Lopinavir/ritonavirBuprenorphineNo significant changeNo dosage adjustment necessary
Lopinavir/ritonavirNaloxoneNo significant changeNo dosage adjustment necessary
NevirapineLumefantrineUnknownNo dosage adjustment necessary
NevirapineTenofovirPotential early virologic failureUse caution when coadministering tenofovir, didanosine, and either efavirenz or nevirapine in treatment-naive patients
RaltegravirFamotidinePossibly owing to increased bioavailability because of ↑ gastric pHNo dosage adjustment necessary
Raltegravir
(400 mg BID)
Omeprazole
(20 mg QD)
Possibly owing to increased bioavailability because of ↑ gastric pHNo dosage adjustment necessary
Raltegravir
(400 mg Q12H)
Omeprazole
(20 mg QD x 4 days)
Possibly owing to increased bioavailability because of ↑ gastric pHNo dosage adjustment necessary