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Home > Treatment > HIV Meds Quarterly > Fall 2009 > ARV Drug Interactions
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 (August-October 2009)
Drug OneDrug TwoClinical EffectsMechanismsManagement
Source: McNicholl I. HIV InSite Database of Antiretroviral Drug Interactions. University of California San Francisco: Center for HIV Information; 2009
AtazanavirFosamprenavir↑ amprenavir effects; ↓ atazanavir effectsPossible induction of CYP450 3A4 by fosamprenavirDo not coadminister
DidanosineBuprenorphineNo dosage adjustment necessary
EtravirineFluconazole↑ etravirine effectsInhibition of CYP450 3A4 by fluconazoleDosage adjustment not established
EtravirineLopinavir/ritonavirPotentially ↓ etravirine effectsPotential induction of CYP450 3A4, 2C9, and 2C19 by lopinavir/ritonavirNo dosage adjustment necessary
EtravirineRaltegravirNo dosage adjustment necessary
EtravirineVoriconazolePossibly ↑ etravirine effectsInhibition of CYP450 3A4 by voriconazoleNo dosage adjustment necessary
Fosamprenavir
(400 mg BID)
Raltegravir
(1,400 mg BID)
Possible induction of p-gpNo dosage adjustment necessary
Fosamprenavir
(400 mg BID)
Raltegravir
(700 mg fosamprenavir BID with 100 mg ritonavir BID)
Possible induction of p-gpNo dosage adjustment necessary
LamivudineBuprenorphineNo dosage adjustment necessary
RaltegravirEfavirenzInduction of UGT1A1 by efavirenzNo dosage adjustment necessary
RaltegravirLamotrigineNo dosage adjustment necessary
RaltegravirRifabutinNo dosage adjustment necessary
RaltegravirRifampinPossibly ↓ raltegravir effectsInduction of UGT1A1 by rifampinDo not coadminister

Alternative agents:
Rifabutin
RaltegravirRitonavirInduction of UGT1A1 by ritonavirNo dosage adjustment necessary
RaltegravirTipranavirInduction of UGT1A1 by tipranavir/ritonavirNo dosage adjustment necessary
Ritonavir
(200 mg BID)
Alprazolam
(1 mg x 1 dose)
↑ alprazolam effects (eg, ↑ sedation, confusion, respiratory depression)Inhibition of CYP450 3A4 by ritonavirAvoid combination; consider alternative agents

Alternative agents:
Lorazepam
RitonavirTriazolam↑ triazolam effects (eg, ↑ sedation, confusion, respiratory depression)Inhibition of CYP450 3A4 by ritonavirAvoid combination; consider alternative agents

Alternative agents:
Lorazepam
Oxazepam
Temazepam
Trazodone
RitonavirZolpidem↑ zolpidem effects (eg, ↑ sedation, confusion)Inhibition of CYP450 3A4 by ritonavirNo dosage adjustment necessary
TenofovirBuprenorphineNo dosage adjustment necessary
TenofovirEthinyl estradiol/
norgestimate
No dosage adjustment necessary