Didanosine Amprenavir

Drugs that should not be combined due to overlapping toxi-cities include amprenavir oral solution plus ritonavir oral solution, atazanavir plus indinavir (due to enhanced hyperbilirubinemia), and any combination of didanosine, stavudine, and zalcitabine. Emtricitabine and lamivudine should not be combined because of their similar chemical structures, and antagonism can result when lamivudine is combined with zalcitabine, or stavudine is combined with zidovudine. 

APV, amprenavir ATV, atazanavir CNS, central nervous system CVD, cardiovascular disease D/C, discontinue ddC, zalcitabine ddl, didanosine DEXA, dual-energy x-ray absorptiometry d4T, stavudine EFV, efavirenz HDL, high-density lipoprotein HIV, human immunodeficiency virus HTN, hypertension IDV, indinavir LDL, low-density lipoprotein LPV/r, lopinavir+ ritonavir MRI, magnetic resonance imaging NNRTI, nonnucleoside reverse transcriptase inhibitor NRTI, nucleoside reverse transcriptase inhibitor NVP, nevirapine PI, protease inhibitor RTV, ritonavir SQV, saquinavir TDF, tenofovir disoproxil fumarate TG, triglyceride TPV/r, tipranivir + ritonavir ZDV, zidovudine. 

Drugs that might affect amprenavir include abacavir, aldesleukin, antacids, anticonvulsants, azole antifungals, clarithromycin, cyclosporine, dexamethasone, buffered didanosine, disulfiram, ethanol, indinavir, methadone, metronidazole, nelfinavir, nonnucleoside reverse transcriptase inhibitors, oral contraceptives, rifamycins, ritonavir, saquinavir, St. John s wort, tacrolimus, and zidovudine. 

Pharmacology Abacavir is a synthetic carbocyclic synthetic nucleoside analog with inhibitory activity against HIV. Abacavir has synergistic activity in combination with amprenavir, nevirapine, and zidovudine and additive activity in combination with didanosine, lamivudine, stavudine, and zalcitabine in vitro. 

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. 

Abacavir (Ziagen) Amprenavir (Agenerase) Delavirdine (Rescriptor) Didanosine [ddl] (Videx) Efavirenz (Sustiva) Efavirenz/Emtricitabine/ Tenofovir (Atripla) Fosamprenavir (Lexiva)... 

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... 

Lopinavir/Ritonavir (Kaletra) [Anrirelroviral/Protease Inhibitor] Uses HIV Infxn Action Protease inhibitor Dose Adults. Tx naive 2 tab PO daily or 1 tab PO bid Tx experiencedpt 1 tab PO bid (T dose if w/ amprenavir, efavirenz, fosamprenavir, nelfinavir, nevirapine) Peds. 7-15 kg 12/3 mg/kg PO bid 15-40 kg 10/2.5 mg/kg PO bid >40 kg Adult dose w/ food Caution [C, /-] Numerous interactions Contra w/drugs dependent on CYP3A/CYP2D6 (Table VI-8) Disp Tab, soln SE Avoid disulfiram (soln has EtOH), metronidazole GI upset, asthenia, T cholesterol/triglycerides, pancreatitis protease metabolic synd Interactions T Effects Wl clarithromycin, erythromycin T effects OF amiodarone, amprenavir, azole andfungals, bepridil, cisapride, cyclosporine, CCBs, ergot alkaloids, flecainide, flurazepam, HMG-CoA reductase inhibitors, indinavir, lidocaine, meperidine, midazolam, pimozide, propafenone, propoxyphene, quinidine, rifabutin, saquinavir, sildenafil, tacrolimus, terfenadine, triazolam, zolpidem 1 effects Wl barbiturates, carbamazepine, dexamethasone, didanosine, efavirenz, nevirapine, phenytoin, rifabutin, rifampin, St. John s wort 1 effects OF OCPs, warfarin EMS Use andarrhythmics and benzodiazepines... 

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. 

Amprenavir PI 1200 mg bid Separate dosing from didanosine or antacids by 1 hour. Avoid high-fat meals. Rash, diarrhea, nausea See footnote 2 for concurrent drug contraindication s. Oral solution contraindicated in young children and pregnant women. 

Amprenavir Abacavir, delavirdine, indinavir, lopinavir, ritonavir, zidovudine Didanosine, efavirenz, nevirapine, saquinavir... 

DIDANOSINE (BUFFERED) PROTEASE INHIBITORS l efficacy of amprenavir, atazanavir and indinavir Absorption of these protease inhibitors may be affected by the buffered didanosine formulation, which t gastric pH Separate doses by at least 1 hour. Alternatively, consider using the enteric-coated formulation of didanosine... 

Shelton MJ, GiovannieUo AA, Cloen D, Berenson CS, Keil K, DiFrancesco R, Hewitt RG. Effects of didanosine formulations on tiie pharmacokinetics of amprenavir. Pharmaco iera-py (2003) 23, 835-42. 

Combination of 16 ARVs seven HIV protease inhibitors (amprenavir, atazanavir, indinavir, lopinavir, nelfmavir, ritonavir, and saquinavir), seven nucleoside reverse transcriptase inhibitors (abacavir, didanosine, emtricitabine, lamivudine, stavudine, zalcitabine, and zidovudine), and two nonnucleoside reverse transcriptase inhibitors (efavirenz and nevirapine)... 

Simultaneous didanosine, folic acid, ganciclovir, lamivudine, nevirapine, pyrazinamide, ranitidine, rifampin, stavudine, sulfamethoxazole, trimethoprim, zidovudine Noninterfering adefovir, amprenavir, delavirdine, efavirenz, fluconazole, indinavir, itraconazole, methadone, nelfinavir, oxazepam, pyrimethamine, rifampin, ritonavir, saquinavir, zalcitabine... 

Aymard, G. Legrand, M. Trichereau, N. Diquet, B. Determination of twelve antiretroviral agents in human plasma sample using reversed-phase high-performance liquid chromatography, J.Chromatogr.B, 2000, 744, 227-240. [for amprenavir efavirenz indinavir nelflnavir ritonavir saquinavir abacavir didanosine lamivudine stavudine nevirapine zidovudine]... 

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