Indinavir Delavirdine

Lopinavir Delavirdine, indinavir, ritonavir, darunavir Fosamprenavir, efavirenz, nelfinavir, nevirapine, tenofovir... 

Saquinavir Atazanavir, delavirdine, indinavir, lopinavir, nelfinavir, tenofovir Efavirenz, nevirapine, tipranavir... 

In vitro studies found quinupristin/dalfopristin inhibited the cytochrome P450 isoenzyme CYP3A4-mediated metabolism of docetaxel, tamoxifen, and terfenadine. Quinupristin/dalfopristin is predicted to raise the levels of other drugs ineluding antiarrhythmics (disopyramide, lidocaine, quinidine), antiretrovirals (such as delavirdine, indinavir, nevirapine, ritonavir), astemizole, carbamazepine, cisapride, methyl-prednisolone, paclitaxel, statins (but see Lipid regulating drugs , (p.l086)), and vinca alkaloids. More study is needed. 

Therapies not recommended for initial treatment due to poor potency or significant toxicity include delavirdine, nevirapine in patients with moderate to high CD4+ T-cell counts, indinavir or saquinavir used without ritonavir ( unboosted ), ritonavir used without another protease inhibitor, and tenofovir plus didanosine with an NNRTI. 

Drugs that may interact with rifabutin include the following Anticoagulants, azole antifungal agents, benzodiazepines, beta blockers, buspirone, corticosteroids, cyclosporine, delavirdine, doxycycline, hydantoins, indinavir, rifamycins, losartan, macrolide antibiotics, methadone, morphine, nelfinavir, quinine, quinidine, theophylline, aminophylline, tricyclic antidepressants, and zolpidem. 

Delavirdine Consider dose reduction of indinavir to 600 mg every 8 hours when administering delavirdine 400 mg 3 times/day. 

Drugs that may affect indinavir include didanosine, aldesleukin, anticonvulsants, atazanavir, nelfinavir, nevirapine, omeprazole, rifapentine, ritonavir, clarithromycin, azole antifungals, rifamycins, delavirdine, efavirenz, St. John s wort. 

Drugs that may affect nelfinavir include anticonvulsants, azithromycin, azole antifungals, efavirenz, delavirdine, HMG-CoA reductase inhibitors, indinavir, interleukins, nevirapine, rifabutin, rifampin, ritonavir, saquinavir, St. John s wort. Drugs that may be affected by nelfinavir include amiodarone, antiarrhythmics (amiodarone, quinidine), azithromycin, benzodiazepines, efavirenz, ergot alkaloids, delavirdine, didanosine, fentanyl, indinavir, lamivudine methadone, nonsedating antihistamines, oral contraceptives, phenytoin, pimozide, quinidine, rifabutin, saquinavir, sildenafil, sirolimus, tacrolimus, zidovudine. 

Drugs that may be affected by delavirdine include the following Clarithromycin, indinavir, amprenavir, benzodiazepines, cisapride, dihydropyridine calcium channel blockers, ergot derivatives, quinidine, sildenafil, warfarin, saquinavir, and didanosine. 

Others Acetaminophen, amiodarone, carbamazepine, delavirdine, efavirenz, nevirapine, quinidine, repaglinide, sildenafil, tadalafil, trazodone, vardenafil Amiodarone, amprenavir, atazanavir, ciprofloxacin, cisapride, clarithromycin, diltiozem, erythromycin, fluconazole, fluvoxamine, grapefruit juice (in high ingestion), indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, norfloxacin, ritonavir, telithromycin, troleandomycin, verapamil, voriconazole Carbamazepine, efavirenz, glucocorticoids, macrolide antibiotics, nevirapine, phenytoin, phenobarbital, rifabutin, rifapentine, rifampin, St. John s wort... 

TC Lamivudine ABC Abacavir d4T Stavudine ddC Zalcitabine ddl Didanosine TDF Tenofovir ZDV Zidovudine, also abbreviated as AZT FTC Emtricitabine NVP Nevirapine DLV Delavirdine EFV Efavirenz RTV, r Ritonavir Pl/r Ritonavir boosted protease inhibitor SQV Saquinavir IDV Indinavir LPV Lopinavir NEV Nelfinavir APV Amprenavir ATV Atazanavir DRV Darunavir... 

Buffering agents that are compounded with didanosine to counteract its degradation by gastric acid may interfere with the absorption of other drugs that require acidity (e.g., indinavir, delavirdine, ketoconazole, fluoroquinolones, tetracyclines, dapsone). An enteric-coated formulation Videx EC) that dissolves in the basic pH of the small intestine is not susceptible to these interactions. Ganciclovir and valganciclovir can increase blood levels of didanosine. The use of zalcitabine with didanosine is not recommended because that combination carries an additive risk of peripheral neuropathy. The combination of didanosine with stavudine increases the risk of pancreatitis, hepatotoxicity, and peripheral neuropa-... 

HIV infection (in combination with other antiretrovirals) PO 800 mg (two 400-mg capsules) q8h. Dosage adjustments when given concomitantly Delavirdine, itraconazole, ketoconazok Reduce dose to 600 mg q8h. Efavirenz-. Increase dose to 1,000 mg q8h. Lopinavir/ritonavir Reduce dose to 600 mg twice a day. Nevirapine-. Increase dose to 1,000 mgqSh. Rifabutin-. Reduce rifabutin by lA and increase indinavir to 1,000 mg q8h. Ritonavir 100-200 mg twice a day and indinavir 800 mg twice a day or ritonavir 400 mg twice a day and indinavir 400 mg twice a day. 

Itraconazole Alfentanil, alprazolam, astemizole, atorvastatin, buspirone, cisapride, cyclosporine, delavirdine, diazepam, digoxin, felodipine, indinavir, loratadine, lovastatin, midazolam, nisoldipine, phenytoin, quinidine, ritonavir, saquinavir, sildenafil, simvastatin, sirolimus, tacrolimus, triazolam, verapamil, warfarin... 

The buffer in didanosine tablets and powder interferes with absorption of indinavir, delavirdine, atazanavir, dapsone, itraconazole, and fluoroquinolone agents therefore, administration should be separated in time. Serum levels of didanosine are increased when -administered with tenofovir or ganciclovir, and are decreased by atazanavir, delavirdine, ritonavir, tipranavir, and methadone (Table 49-4). 

Fosamprenavir Abacavir, atazanavir, delavirdine, etravirine, indinavir, lopinavir, ritonavir, tipranavir, zidovudine Didanosine, efavirenz, nevirapine, saquinavir... 

Indinavir Delavirdine, nelfinavir, ritonavir, zidovudine, darunavir Fosamprenavir, didanosine, efavirenz, etravirine, nevirapine... 

Nelfinavir Fosamprenavir, delavirdine, efavirenz, indinavir, ritonavir, saquinavir ... 

Drugs that may inhibit cytochrome P450 metabolism of other drugs include amiodarone, androgens, atazanavir, chloramphenicol, cimetidine, ciprofloxacin, clarithromycin, cyclosporine, delavirdine, diltiazem, diphenhydramine, disulfiram, enoxacin, erythromycin, fluconazole, fluoxetine, fluvoxamine, furanocoumarins (substances in grapefruit juice), indinavir, isoniazid, itraconazole, ketoconazole, metronidazole, mexile-tine, miconazole, nefazodone, omeprazole, paroxetine, propoxyphene, quinidine, ritonavir, sulfamethizole, verapamil, voriconazole, zafirlukast, and zileuton. 

At the present time, there are at least 14 compounds that have been formally approved for the treatment of human immunodeficiency virus (HIV) infections. There are six nucleoside reverse transcriptase inhibitors (NRTIs) that, after their intracellular conversion to the 5 -triphosphate form, are able to interfere as competitive inhibitors of the normal substrates (dNTPs). These are zidovudine (AZT), didanosine (ddl), zalcitabine (ddC), stavudine (d4T), lamivudine (3TC), and abacavir (ABC). There are three nonnucleoside reverse transcriptase inhibitors (NNRTIs) — nevirapine, delavirdine, and efavirenz — that, as such, directly interact with the reverse transcriptase at a nonsubstrate binding, allosteric site. There are five HIV protease inhibitors (Pis saquinavir, ritonavir, indinavir, nelfinavir, and amprenavir) that block the cleavage of precursor to mature HIV proteins, thus impairing the infectivity of the virus particles produced in the presence of these inhibitors. 

Indinavir Delavirdine, lopinavir, nelfinavir, zidovudine Amprenavir, delavirdine, efavirenz, nevirapine, ritonavir... 

Ritonavir Delavirdine, efavirenz Didanosine, indinavir, zidovudine... 

Delavirdine is extensively metabolized to inactive metabolites by the CYP3A and CYP2D6 enzymes. However, it also inhibits CYP3 A and thus inhibits its own metabolism. In addition to its interactions with other antiretroviral agents (see Table 49 1), delavirdine will result in increased levels of numerous agents (Table 49-3). Dose reduction of indinavir and saquinavir should be considered if they are administered concurrently with delavirdine. Delavirdine plasma concentrations are reduced in the presence of antacids, phenytoin, phenobarbital, carbamazepine, rifabutin, and rifampin concentrations are increased during coadministration with clarithromycin, fluoxetine, dexamethasone, and ketoconazole. 

Since indinavir is a substrate as well as an inhibitor of CYP3 A4, numerous and complex drug interactions can occur as described above. Indinavir levels decrease with concurrent use of rifabutin, fluconazole, St. John s wort, and rifampin. Caution is advised with other 3 A4 inducers also, including phenobarbital, phenytoin, carbamezepine, and dexamethasone. Dose reduction of indinavir should be considered if coadministered with delavirdine, ketoconazole, or itraconazole, while an increase in the dose of indinavir is indicated if the drug is coadministered with efavirenz or rifabutin. 

By inhibiting their metabolism, ritonavir potentiates the actions of other protease inhibitors. The addition of delavirdine instead of another NNRTI in three patients taking protease inhibitors plus ritonavir further increased the exposure to the protease inhibitors (6). Combining delavirdine with indinavir removes the food restrictions during indinavir administration (4). The superior virological response observed in antiretroviral regimens containing delavirdine and protease inhibitors has been attributed in part to the pharmacokinetic interaction. 

Lipemia retinalis and pancreatitis have been reported in a 39-year-old man with HIV infection associated with protease inhibitor therapy (13). He developed lipemia retinahs after switching to an antiretroviral regimen including ritonavir and saquinavir (together with zalci-tabine and delavirdine). He had previously been taking zidovudine, lamivudine, and indinavir. 

Clinically important, potentially hazardous interactions with alcohol, aprepitant, clarithromycin, CNS depressants, delavirdine, digoxin, efavirenz, fluconazole, fluoxetine, fluvoxamine, grapefruit juice, indinavir, itraconazole, ivermectin, kava, ketoconazole, propoxyphene, ritonavir, saquinavir, St John s wort... 

Clinically important, potentially hazardous interactions with almotriptan, amprenavir, clarithromycin, darunavir, delavirdine, efavirenz, erythromycin, fosamprenavir, indinavir, naratriptan, nelfinavir, nilotinib, ritonavir, rizatriptan, saquinavir, sibutramine, sumatriptan, telithromycin, tipranavir, troleandomycin, zolmitriptan... 

---